U.S. patent application number 14/035103 was filed with the patent office on 2014-01-23 for method of grouping and analyzing clinical risks.
This patent application is currently assigned to 3M INNOVATIVE PROPERTIES COMPANY. The applicant listed for this patent is 3M INNOVATIVE PROPERTIES COMPANY. Invention is credited to Richard F. Averill, Jon Eisenhandler, Norbert I. Goldfield.
Application Number | 20140025395 14/035103 |
Document ID | / |
Family ID | 23167330 |
Filed Date | 2014-01-23 |
United States Patent
Application |
20140025395 |
Kind Code |
A1 |
Averill; Richard F. ; et
al. |
January 23, 2014 |
METHOD OF GROUPING AND ANALYZING CLINICAL RISKS
Abstract
A method of creating a classification system for rating the
nature and severity of health care requirements, including
obtaining a set of medical disease codes, categorizing the medical
disease codes into major disease categories, and categorizing the
medical disease codes in each major disease category into episode
disease categories based on severity.
Inventors: |
Averill; Richard F.;
(Seymour, CT) ; Eisenhandler; Jon; (Bristol,
CT) ; Goldfield; Norbert I.; (Northampton,
MA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
3M INNOVATIVE PROPERTIES COMPANY |
St. Paul |
MN |
US |
|
|
Assignee: |
3M INNOVATIVE PROPERTIES
COMPANY
St. Paul
MN
|
Family ID: |
23167330 |
Appl. No.: |
14/035103 |
Filed: |
September 24, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11465901 |
Aug 21, 2006 |
8571892 |
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14035103 |
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09302336 |
Apr 29, 1999 |
7127407 |
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11465901 |
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Current U.S.
Class: |
705/2 |
Current CPC
Class: |
G16H 10/40 20180101;
G16H 50/70 20180101; G16H 10/60 20180101; G16H 50/30 20180101; G06Q
40/02 20130101; G06Q 40/08 20130101; G06Q 10/10 20130101 |
Class at
Publication: |
705/2 |
International
Class: |
G06F 19/00 20060101
G06F019/00 |
Goverment Interests
STATEMENT OF GOVERNMENT RIGHTS
[0002] This invention was made with United States Government
support under Cooperative Agreement Award no. 70NANB5H1013 awarded
by the National Institute of Standards and Technology. The United
States Government has certain rights in the invention.
Claims
1. A method of rating the nature and severity of health care
requirements for an individual, including: (a) providing a computer
system storing a set of medical disease codes, wherein the medical
disease codes are categorized into major disease categories,
wherein the medical disease codes in each major disease category
are categorized into episode disease categories based on severity
of health care requirements, wherein at least some of the episode
disease categories are sub-divided by severity of illness level by
using severity of illness rules, and wherein the computer system
further stores overall clinical risk group criteria for assigning
an overall clinical risk group to an individual patient, where the
overall clinical risk group criteria takes into account the episode
disease categories and severity of illness levels; (b) obtaining
historical care data for an individual; (c) determining the episode
disease categories for the individual; (d) assigning severity
levels to the episode disease categories for the individual; and
(e) assigning an overall clinical risk group to an individual based
on the overall clinical risk group criteria.
2. The method of claim 1 wherein the severity of illness rules take
into account other episode disease categories or other information
not related to a particular episode disease category being
subdivided.
3. The method of claim 1 wherein the overall clinical risk group
criteria adjusts for the effect of interacting conditions in
different episode disease categories.
4. The method of claim 1 wherein the step of assigning severity
levels to the episode disease categories for the individual is
based on the nature and temporal relationships of the episode
disease categories experienced by the individual.
5. The method of claim 1, further comprising defining severity of
illness levels for each clinical risk group taking into account
episode disease categories.
6. The method of claim 1, further comprising defining severity of
illness levels for each clinical risk group taking into account
prescription drug usage.
7. The method of claim 1, wherein the severity of illness rules
adjust the severity of illness level for each episode disease
category based on the nature and timing of treatment for each
episode disease category.
8. The method of claim 8, wherein the severity of illness rules
adjust the severity of illness level for each episode disease
category based on the recency of other episode disease
categories.
9. The method of claim 1, further comprising: a) obtaining a set of
medical procedure codes for the individual; b) categorizing the
medical procedure codes into episode procedure categories; wherein
the severity of illness rules take account of the episode procedure
categories in adjusting the severity of illness level for each
episode disease category.
10. The method of claim 9 wherein medical procedure codes include
prescription drug usage codes.
11. The method of claim 9, further comprising the step of
determining episode disease categories for the individual that are
indicated by the episode procedure categories.
12. The method of claim 1, further comprising selecting a primary
chronic disease or identifying a lack of a primary chronic disease
from the episode disease categories for each major disease category
based on a set of selection criteria.
13. The method of claim 12, wherein the computer system further
stores a risk group criteria for each of a series of risk groups,
wherein the series of risk groups are ranked in order of clinical
significance, and further comprising the step of comparing the
episode disease categories to the risk group criteria for each risk
group, and assigning the most severe clinical risk group for which
the criteria are met.
14. The method of claim 1, wherein the computer system further
stores a criteria for assigning an overall clinical risk group to a
group of patients, where the criteria for assigning an overall
clinical risk group to a group of patients takes into account the
episode disease categories and severity of illness levels.
15. The method of claim 1, further comprising adjusting the episode
disease categories for the individual based on the nature and
temporal relationships of the episode disease categories
experienced by the individual.
16. The method of claim 15, wherein the adjusting step includes
deleting episode disease categories when the temporal relationship
between events implies that the disease indicated by an episode
disease category has likely been eliminated by subsequent
treatment.
17. The method of claim 16, further comprising the steps of: a)
assigning a clinical risk group to the individual based on the
adjusted episode disease categories experienced by the individual;
b) identifying from adjusted episode disease categories the primary
chronic disease in each major disease categories; and c)
determining the clinical risk group based on the number and type of
primary chronic diseases.
18. The method of claim 17, wherein the step of determining the
clinical risk group is further based on the presence of
catastrophic conditions.
19. The method of claim 17, further comprising the steps: a)
determining the severity of illness level for each primary chronic
disease experienced by the individual; b) setting a severity of
illness level for each primary chronic disease based on the nature,
temporal relationships and severity of illness levels of the
episode disease categories experienced by the individual; and c)
assigning an overall severity of illness for the individual based
on the adjusted severity of illness levels for the primary chronic
diseases experienced by the individual.
20. A computer system for rating the nature and severity of health
care requirements for an individual, including: (a) a storage
device storing: (i) a set of medical disease codes, wherein the
medical disease codes are categorized into major disease
categories, wherein the medical disease codes in each major disease
category are categorized into episode disease categories based on
severity of health care requirements, wherein at least some of the
episode disease categories are sub-divided by severity of illness
level by using severity of illness rules, and wherein the computer
system further stores overall clinical risk group criteria for
assigning an overall clinical risk group to an individual patient,
where the overall clinical risk group criteria takes into account
the episode disease categories and severity of illness levels; and
(ii) historical care data for an individual; and (b) a processing
unit configured for: (i) determining the episode disease categories
for the individual; (ii) assigning severity levels to the episode
disease categories for the individual; and (iii) assigning an
overall clinical risk group to an individual based on the overall
clinical risk group criteria.
21. The system of claim 20 wherein the severity of illness rules
take into account other episode disease categories or other
information not related to a particular episode disease category
being subdivided.
22. The system of claim 20 wherein the overall clinical risk group
criteria adjusts for the effect of interacting conditions in
different episode disease categories.
23. The system of claim 20 wherein assigning severity levels to the
episode disease categories for the individual is based on the
nature and temporal relationships of the episode disease categories
experienced by the individual.
24. The system of claim 20, wherein the processing unit is further
configured for defining severity of illness levels for each
clinical risk group taking into account episode disease
categories.
25. The system of claim 20, wherein the processing unit is further
configured for defining severity of illness levels for each
clinical risk group taking into account prescription drug
usage.
26. The system of claim 20, wherein the severity of illness rules
adjust the severity of illness level for each episode disease
category based on the nature and timing of treatment for each
episode disease category.
27. The system of claim 26, wherein the severity of illness rules
adjust the severity of illness level for each episode disease
category based on the recency of other episode disease
categories.
28. The system of claim 20, further comprising: a) obtaining a set
of medical procedure codes for the individual; b) categorizing the
medical procedure codes into episode procedure categories; wherein
the severity of illness rules take account of the episode procedure
categories in adjusting the severity of illness level for each
episode disease category.
29. The system of claim 28 wherein medical procedure codes include
prescription drug usage codes.
30. The system of claim 28, wherein the processing unit is further
configured for determining episode disease categories for the
individual that are indicated by the episode procedure
categories.
31. The system of claim 20, wherein the processing unit is further
configured for selecting a primary chronic disease or identifying a
lack of a primary chronic disease from the episode disease
categories for each major disease category based on a set of
selection criteria.
32. The system of claim 31, wherein the storage device further
stores a risk group criteria for each of a series of risk groups,
wherein the series of risk groups are ranked in order of clinical
significance, and wherein the processing unit is further configured
for comparing the episode disease categories to the risk group
criteria for each risk group, and assigning the most severe
clinical risk group for which the criteria are met.
33. The system of claim 20, wherein the storage device further
stores a criteria for assigning an overall clinical risk group to a
group of patients, where the criteria for assigning an overall
clinical risk group to a group of patients takes into account the
episode disease categories and severity of illness levels.
34. The system of claim 20, wherein the processing unit is further
configured for adjusting the episode disease categories for the
individual based on the nature and temporal relationships of the
episode disease categories experienced by the individual.
35. The system of claim 34, wherein the processing unit is
configured for, when adjusting the episode disease categories,
deleting episode disease categories when the temporal relationship
between events implies that the disease indicated by an episode
disease category has likely been eliminated by subsequent
treatment.
36. The system of claim 35, wherein the processing unit is further
configured for: a) assigning a clinical risk group to the
individual based on the adjusted episode disease categories
experienced by the individual; b) identifying from adjusted episode
disease categories the primary chronic disease in each major
disease categories; and c) determining the clinical risk group
based on the number and type of primary chronic diseases.
37. The system of claim 35, wherein the processing unit is further
configured for determining the clinical risk group further based on
the presence of catastrophic conditions.
38. The system of claim 35, wherein the processing unit is further
configured for: a) determining the severity of illness level for
each primary chronic disease experienced by the individual; b)
setting a severity of illness level for each primary chronic
disease based on the nature, temporal relationships and severity of
illness levels of the episode disease categories experienced by the
individual; and c) assigning an overall severity of illness for the
individual based on the adjusted severity of illness levels for the
primary chronic diseases experienced by the individual.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. Ser. No.
11/465,901, filed Aug. 21, 2006, now allowed, which is a divisional
of U.S. Ser. No. 09/302,336, filed Apr. 29, 1999, now U.S. Pat. No.
7,127,407, the disclosure of which is herein incorporated by
reference.
BACKGROUND OF THE INVENTION
[0003] 1. Technical Field
[0004] The present invention relates to risk/cost analysis tools
for estimating future health care costs, and in particular to tools
for retrospective review and profiling to create risk groups.
[0005] 2. Description of the Related Art
[0006] Estimates of the anticipated health care requirements and
costs for a group of patients may be used for a variety of
purposes, most notably anticipating costs for insurance and other
purposes related to the financing of health care. Estimates
typically are made by analyzing the historical records of the
members of the population for which the estimate is being made and
extrapolating future health care requirements from clinical and
other defined characteristics of the population. Systems for doing
this are generally referred to as risk adjusters, since they
categorize individuals based on their future risk for needing
health care services. However, the risk adjusters to date have
operated only at a high level, with the result that their efficacy
and utility is limited.
[0007] In early risk adjusters, weights were calculated for each of
a set of diagnostic categories and/or cost groups using a linear
regression model. Only a single category, the most expensive, is
chosen to estimate an individual's future costs and all other
diagnoses are ignored. While a single factor clearly is inadequate
for individuals with multiple problems, an additive approach is
occasionally used. Currently available products, such as
Hierarchical Coexisting conditions (HCC), determine the weight
given each disease group using a linear regression model which
assigns a weight for each of a set of diagnostic categories. Then,
where and when applicable, the weights for each diagnostic category
in an individual's history are added to get a total weight. The
total weight is converted into a predicted cost for the next year.
Additive approaches, however, may also not accurately represent the
relationship between ostensibly independent problems. For example,
consider the case of individuals with diabetes and hypertension,
which generally are considered independent but interactive disease
processes. While diabetes does not cause hypertension, or vice
versa, it is not unusual for an individual to have both. However,
the additional or marginal cost for treating a diabetic with
hypertension may actually be considerably less than simply adding
the cost for treating a non-hypertensive diabetic to the cost for
treating a non-diabetic hypertensive. This makes intuitive sense
when one considers that the diabetic already is making regular
office visits for the diabetes, blood pressure is routinely checked
during any medical office visit, so the costs are likely not equal
to the costs of treating diabetes and hypertension
independently.
[0008] Some past risk adjustment systems (e.g., the Medicare
Diagnosis Related Groups, or DRGs) include some historical
indication of overall severity at a particular time in a particular
setting, but they do not explicitly identify severity by category
of disease or project its likely impact upon medical needs into the
future. The severity level of a disease can directly affect how
that disease interacts with other diseases, and the consequent need
for future care. To continue with the example just described, the
example probably is true for low severity diabetes and low severity
hypertension, but the opposite may be true for high severity
diabetes and high severity hypertension. When both diseases are
high severity, they can interact, making both diseases harder to
treat. A system not explicitly incorporating severity into its
logic will not identify this interaction risk.
[0009] Estimating costs using weights reflecting individuals from
different points in the disease process also can be misleading.
Individual health care needs vary not only by disease, but also by
severity of disease. For example, at least in its early stages,
hypertension is a relatively minor condition for many people,
controllable by diet and exercise. However, for people in more
advanced stages, it may be a fairly serious problem. It may require
aggressive treatment, including occasional hospitalization, as well
as posing a high risk of other significant cardiovascular problems.
A single weight will not accurately reflect the severity of a
disease experienced by individuals at different stages of the
disease. No current risk adjustment system explicitly identifies
levels of severity of disease.
[0010] Current systems also ignore the temporal aspects of care,
such as treatment which may eliminate prior problems. For example,
a patient with angina who undergoes a coronary arterial bypass
graft (CABG) would not be expected to experience a recurrence of
angina in the period following the bypass. But current systems do
not take this into account--if angina has been recorded at any
time, they continue to assume angina is present until such time as
it no longer appears in the data.
[0011] The current systems, such as that in U.S. Pat. No.
5,557,514, were designed to predict future costs to allow
calculation of insurance rates and identification of providers with
high utilization profiles, but are of limited value to in helping
providers to actually control costs. The capitated payment
arrangements typical of health maintenance organizations and
preferred provider organizations place the majority of financial
risk on the providers of care. The underlying assumption is that
since providers are responsible for the delivery of care, they can
respond to the incentives to control costs inherent in a capitated
payment system.
[0012] The success of any payment system that is predicated on
providing incentives for cost control is almost totally dependent
on the effectiveness with which the incentives are communicated to
providers. Payers need to express the payment arrangements in a
form that communicates the incentives in the system in a manner and
at a level of detail that promotes effective management
responses.
[0013] But detailed clinical descriptions are not considered in
current systems, and, more importantly, explicit severity levels
and interactions among clinical conditions are not a part of a
group assignment. Therefore, data from such systems is of limited
value to clinicians, who need to understand the clinical basis of
their costs in order to respond effectively to incentives inherent
in capitated payment systems. While it sometimes is possible to use
the information from such risks adjuster to identify where
pro-active efforts could substantially reduce problems (and costs),
it is very difficult.
SUMMARY OF THE INVENTION
[0014] In one aspect, the present invention provides a method of
creating a classification system for rating the nature and severity
of health care requirements, including obtaining a set of medical
disease codes, categorizing the medical disease codes into major
disease categories, and categorizing the medical disease codes in
each major disease category into episode disease categories based
on severity. This method further includes sub-dividing at least
some of the episode disease categories by severity of illness level
by using severity of illness rules to take into account other
episode disease categories or other information not related to a
particular episode disease category being subdivided and defining
criteria for assigning an overall clinical risk group to an
individual patient, where the criteria takes into account the
episode disease categories and severity of illness levels, where
the criteria adjusts for the effect of interacting conditions in
different episode disease categories.
[0015] In another aspect, the present invention provides a method
of creating a classification system for rating the nature and
severity of health care requirements, including obtaining a set of
medical disease codes, categorizing the medical disease codes into
major disease categories, and categorizing the medical disease
codes into episode disease categories in each major disease
category based on severity. This method further includes obtaining
a set of medical procedure codes, categorizing the medical
procedure codes into episode procedure categories, and sub-dividing
at least some of the episode disease categories by severity of
illness level by using severity of illness rules, wherein the
severity of illness rules take into account temporal information
including order of occurrence of the episode disease categories and
episode procedure categories.
[0016] In another aspect the invention provides a method of
creating a classification system for rating the nature and severity
of health care requirements, including first, obtaining a set of
medical disease codes and second, categorizing the medical disease
codes into major disease categories, wherein each major disease
category corresponds to a single organ system, a malignancy or a
multiple trauma. The method further includes third, categorizing
the medical disease codes in each major disease category into
episode disease categories based on severity and fourth,
sub-dividing at least some of the episode disease categories by
severity of illness level by using severity of illness rules,
thereby defining a set of severity of illness levels for each
episode disease category.
[0017] The above summary of the present invention is not intended
to describe each disclosed embodiment or every implementation of
the present invention. The Figures and the detailed description
which follow more particularly exemplify illustrative
embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] The preferred embodiments of the invention will be described
in connection with the drawings, in which:
[0019] FIG. 1 is a schematic of a computer system by which the
method of the present invention might be implemented.
[0020] FIGS. 2-4 are flow charts schematically illustrating the
steps of the preferred embodiments of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0021] The present invention creates a comprehensive set of risk
groups which in particular explicitly identifies groups of
individuals with multiple interacting co-morbid conditions, and
which explicitly identifies the severity of illness level. This
allows accurate prediction of future health care resource needs of
an entire population, while simultaneously helping the health care
provider isolate problems to identify changes in care to reduce
costs and improve quality.
[0022] The present invention starts this process by developing a
classification system that rates both the nature and severity of
health care requirements, then applies that system to historical
information for both individual patients and populations to group
them according clinical risks. Each individual will fall into a
single, mutually exclusive risk group in the classification system.
Each risk group relates the historical clinical and demographic
characteristics of the individual to the amount and type of health
care resources that individual likely will consume in the future.
Since the clinical risk groups are clinically based, they create a
system that links the clinical and financial aspects of care. Thus,
the clinical risk groups are designed to serve as the foundation of
management systems which support care pathways, product line
management and case management.
[0023] The present invention assumes there is at least one set of
medical care codes available which is used to describe patient
treatment. According to the present invention, the classification
system is created by categorizing the medical care codes into major
disease categories, and subdividing each major disease category
into a plurality of episode disease categories based on the
severity and/or longevity of the disease. The episode disease
categories within each major disease category are ranked in
seriousness, with, e.g., chronic diseases (e.g., emphysema) rated
more severely than acute diseases which by their nature usually
will last only a short while (e.g., pneumonia). In addition,
severity of illness levels preferably are defined for episode
disease categories.
[0024] In the typical situation, there in fact will be multiple
sets of medical care codes, e.g., one used by hospitals and one
used by physicians. Each of them can be categorized into its own
sets of categories, though the level of detail applied may vary by
set. For example, hospitals tend to have a far larger number of
codes than physicians, so a more detailed categorization would be
appropriate.
[0025] The classification system is applied to a set of historical
data for an individual patient by first identifying all episode
disease categories experienced by that individual. The episode
disease categories within each major disease category are then
adjusted to take into account to take into account the nature and
timing of treatment events. For example, an individual with a
history of angina, who then has angioplasty, can be expected to not
have angina in the future. The episode disease category for angina
therefore should be deleted, unless the angina has recurred some
significant period of time (e.g., 90 days) after the angioplasty.
Note that the information from multiple sets of codes may interact
in this adjustment (e.g., angina often will be identified from
physician records, while angioplasty will normally be identified
from hospital records). The severity of illness is adjusted in a
similar manner.
[0026] Once the episode disease categories have been defined and
severity of illness adjusted, the primary chronic disease is
identified for each major disease category. The severity of illness
for each major disease category typically will be the same as that
for the primary chronic disease, but may need to be adjusted if
there are episode disease categories in other major disease
categories which interact with it, e.g., amputation of extremities
implies that a patient with diabetes is in an extremely advanced
state of diabetes, which may be even worse if the patient also has
congestive heart failure.
[0027] The major disease categories and their respective severity
of illnesses then are aggregated in a similar fashion to identify a
single clinical risk group for the individual, and an overall
severity of illness for the individual.
[0028] The classification system then also defines a method for
aggregating information about groups of patients, to allow the
summation of information about large numbers of patients.
Preferably, this involves grouping the clinical risk groups into
aggregated clinical risk groups at a variety of levels.
[0029] A significant advantage to the present invention is that it
allows health care providers to identify and pro-actively treat
health problems. Unlike present capitation rate calculation
systems, the clinical risk groups developed and used according to
the present invention directly communicate information in a form
and at a level of details that can lead to specific positive
actions. To illustrate the difference, suppose that for individuals
with diabetes the capitated payments are 25% lower than the
provider's expenditures. While this is obviously useful information
for identifying a problem, it does not give the provider any real
information on the precise source of the problem, or the actions
that can be taken to correct the problem. In contrast, suppose the
payment system also provided the following information: [0030] "The
higher costs for diabetic individuals are due to unusually high
expenditures for inpatient care combined with uncommonly low
expenditures for pharmacy and outpatient laboratory services for
severity of illness level 1 and 2 diabetic individuals. Further a
higher than expected percentage of severity of illness level 1 and
2 diabetic individuals over time become severity level 3 or 4."
Clearly, the above information raises specific questions concerning
the monitoring and preventive care being provided to individuals
with low severity diabetes, which gives providers a basis for
management action, and an effective response to the incentives in
the payment system.
[0031] Another significant advantage of the present invention is
that it allows much more accurate estimations of future health care
needs and costs. Given a large sample size, it is quite
straightforward to determine the typical future costs for each
individual in a particular clinical risk group. Those costs then
can be used to weight the total cost of a group, based on the
number of individuals in each clinical risk group. Similarly, the
clinical risk group information can also be used to develop much
more accurate predictions of future capital equipment needs,
personnel needs and the like.
[0032] Almost all payers for health care (the government, insurance
companies, self-insured companies, etc.) require providers to
report on the services for which they are seeking reimbursement
using coding schemes, thereby allowing the payers to process the
requests for payment efficiently. Most hospitals use the
International Classification of Diseases, 9th Revision, Clinical
Modifications (ICD-9-CM), to code diagnoses, signs, symptoms,
findings and other factors influencing health status. Most
professional services and procedures performed in an ambulatory
setting are reported using Current Procedural Terminology (CPT)
codes and the Health Care Financing Administration (HCFA) Common
Procedure Coding Systems (HCPCS), which includes the CPT codes. The
present invention therefore will be described with reference to the
ICD-9-CM, CPT and HCPCS codes. However, it will be understood that
the present invention could be used with any other suitably
detailed coding scheme, and that these coding systems are being
used simply because they will be familiar to one of skill in the
art.
[0033] The present invention analyzes coded medical histories into
Clinical Risk Groups (CRGs). Almost of necessity given the size of
the databases involved, the process will be implemented in a
computer-based system such as that shown in FIG. 1. In FIG. 1, the
computer system 100 includes a central processing unit (CPU) 110,
random access memory (RAM) 120, mass storage device 130 (such as a
hard drive, CD drive, diskette drive or the like), a display 140
(such as a cathode ray tube, LED, LCD or plasma display) and a
printer 150 (such as a dot matrix printer, a laser printer, or an
ink jet printer), associated such that the CPU can read and write
to the RAM 120 and the mass storage device 130, can control the
images on the display 140 and the output of the printer 150.
[0034] The computer system 100 implements the CRG clinical logic
based on a five step or phase process:
Phase I A disease profile and history of past medical interventions
is created. Phase II In each organ system, the most significant
chronic disease under active treatment is identified Phase III In
each organ system, the severity of illness level of the most
significant chronic disease under active treatment is determined
Phase IV The most significant chronic disease under active
treatment and its associated severity of illness level are combined
to determine the overall Base CRG and severity of illness level for
the individual Phase V The overall Base CRG and severity of illness
level are consolidated into three successive tiers of
aggregation
[0035] As will be seen, the five phase process for determining the
CRG assignment identifies individuals with multiple interacting
co-morbid diseases and their associated severity of illness
level.
Classifications:
[0036] The present invention requires creation of a series of
classifications, which are generated iteratively--set up a
classification, run test data, analyze the results, modify the
classification and repeat. There is no one correct set of
classifications--the particular classifications will change with
advancing medical knowledge and other changes affecting the
practice of medicine. Therefore what will be described is the
process of creating such a classification system.
[0037] In the ICD-9-CM, the term disease is used to encompass
diagnoses, signs, symptoms, findings and other factors influencing
health status. There are approximately 12,000 codes in the current
version of ICD-9-CM. For brevity the ICD-9-CM codes will be
referred to simply as disease codes.
[0038] Starting with step 200 in FIG. 2, each of the disease codes
in the ICD-9-CM are categorized in step 205 into a series of
mutually exclusive and exhaustive categories referred to as Major
Disease Categories (MDCs). The diseases in each MDC correspond to a
single organ system (e.g., respiratory system, digestive system,
etc.) or etiology (e.g., malignancies, systemic infectious
diseases, etc.). With the exception of malignancies and multiple
trauma, which are each assigned to their own MDC, diseases that
include both a particular organ system and a particular etiology
(e.g., pneumonia) are assigned to the MDC corresponding to the
organ system involved. Systemic infections such as septicemia, are
assigned to the systemic infections disease MDC. Some diagnoses are
considered catastrophic (e.g., persistent vegetative state) and are
assigned to a catastrophic MDC. An example of a set of 31 MDCs
meeting these criteria is shown in Table 1.
TABLE-US-00001 TABLE 1 List of MDCs Class Description 1 Nervous
System Diseases 2 Eye Diseases 3 Ear, Nose, Mouth And Throat
Diseases 4 Cranial Facial Anomalies 5 Respiratory Diseases 6 Heart
And Cardiac Vascular Diseases 7 Peripheral And Non-Cardiac Vascular
Diseases 8 Digestive Diseases 9 Hepatobiliary & Pancreas
Diseases 10 Musculoskeletal Diseases 11 Connective Tissue Diseases
12 Skin, Subcutaneous Tissue & Breast Diseases 13 Diabetes 14
Endocrine, Metabolic And Thyroid Diseases Except Diabetes 15 Kidney
And Urinary Tract Diseases 16 Male Reproductive Diseases 17 Female
Reproductive Diseases 18 Pregnancy, Childbirth And The Puerperium
19 Newborns And Other Neonates 20 Chromosomal Anomalies, Mental
Retardation & Other Developmental Cognitive Diseases 21 Blood
And Blood Forming Organ Diseases 22 Malignancies 23 Systemic
Infectious And Parasitic Diseases 24 Mental Diseases 25 Substance
Abuse 26 Injuries, Poisoning And Toxic Effects Of Drugs 27 Burns 28
Factors Influencing Health Status And Other Contacts With Health
Services 29 HIV Infection 30 Multiple Significant Trauma 31
Catastrophic Conditions
[0039] The diagnoses in each MDC are further subdivided into
Episode Disease Categories (EDCs) in step 210. Each EDC is assigned
to one of a number of EDC types, which rate the severity and
persistence of the disease.
[0040] In a preferred embodiment, there are six EDC types. Four of
the EDC types relate to chronic diseases and two of the EDC types
relate to acute diseases. A disease is classified as chronic if the
duration of the disease is life long (e.g., cystic fibrosis).
Diseases which have a prolonged duration, but for which a cure
(i.e., no evidence of the disease) is possible, are considered
chronic (e.g., malignancies). Life long or prolonged diseases
controlled by medication or other means (e.g., hypertension) are
also considered chronic. A disease is classified as acute if the
duration of the disease is short and the disease would naturally
resolve (e.g., pneumonia) or there is a treatment which cures the
disease (e.g., fractured leg). Signs, symptoms and findings (e.g.,
chest pain) in general are considered acute, even though they might
be indicative of a chronic problem. The six preferred EDC types are
defined as follows: [0041] Dominant Chronic EDCs: Serious chronic
diseases which usually result in the progressive deterioration of
an individual's health and often times lead to, or significantly
contribute to an individual's need for medical care, debility and
death. (e.g., congestive heart failure, diabetes). [0042] Moderate
Chronic EDCs: Serious chronic diseases which, usually do not result
in the progressive deterioration of an individual's health but can
significantly contribute to an individual's need for medical care,
debility and death (e.g., asthma, epilepsy). [0043] Minor Chronic
EDCs: Chronic diseases which may be serious in their advanced
stages or may be a precursor to more serious diseases (e.g.,
hyperlipidemia), but can usually be managed effectively throughout
an individual's life with few complications and minimal effect upon
an individual's need for medical care, debility and death (e.g.,
migraine headache, hearing loss). [0044] Chronic Manifestation
EDCs:A manifestation or acute exacerbation of a chronic disease
(e.g., diabetic neuropathy). The chronic manifestation EDC
describes manifestation or acute exacerbation (i.e., the
neuropathy) and indicates the presence of the underlying chronic
disease (i.e., diabetes). In addition, they are used to identify
uncommon, but distinct, disease within a more frequently occurring
EDC and are used to determine the severity level of the EDC, and
for management reporting. [0045] Significant Acute EDCs: Serious
acute illness which can be a precursor to or place the individual
at risk for the development of chronic disease (e.g., chest pain)
or can result in significant sequelae (e.g., head injury with
coma). [0046] Minor Acute EDCs: Minor acute illnesses are self
limiting, are not a precursor to chronic disease, do not place the
individual at risk for the development of chronic disease and do
not result in significant sequelae (e.g., fractured arm, common
cold).
[0047] The categorization of an EDC as chronic or acute is an
important distinction because individuals who have chronic EDCs
from multiple organ systems (i.e., MDCs) are assigned to a distinct
set of CRGs. Some diseases that are generally considered chronic
can, under certain conditions, be an acute disease. For example,
congestive heart failure is generally considered a chronic disease.
However, congestive heart failure that occurs in children is
usually associated with an underlying congenital anomaly which can
be corrected by surgery. Therefore, in children congestive heart
failure typically would be considered an acute disease. But even
this has an exception if the congestive heart failure is due to
rheumatic fever, which would always be considered chronic.
Similarly, hypertension is generally considered a chronic disease.
However, because there is the possibility that a single high blood
pressure reading could be miscoded as hypertension, hypertension is
considered an acute disease unless the hypertension recurs at least
twice over a period of time that spans at least 90 days. Thus, some
diseases generally considered chronic are only categorized as
chronic under certain conditions.
[0048] As noted above, procedures performed in hospitals usually
are reported using ICD-9-CM procedure codes. Professional services,
and procedures performed in an ambulatory setting typically are
reported more often as the Current Procedural Terminology (CPT)
codes. Prescription drug usage may also be reported in a coded
fashion. Like ICD-9-CM codes, at step 215 such procedural codes can
be categorized in step 220 according to the present invention into
mutually exclusive and exhaustive categories, referred to as
Episode Procedure Categories (EPCs). The EPCs can be used to
identify individuals who are dependent on some medical technology
(e.g., dialysis), who had a procedure that is indicative of
advanced disease (e.g., leg amputation) or who had a procedure that
has long term sequelae (e.g., heart transplant).
[0049] The occurrence of EPCs that are indicative of advanced
disease or that have long term sequelae are used in step 223 to
create a chronic EDC that specifies a history of the procedure
(e.g., history of heart transplant). Normally, no distinction need
be made between chronic EDCs associated with the history of a
procedure (created in step 223) and chronic EDCs associated with a
disease (created in step 210).
[0050] As will be apparent, there usually will be hundreds of
mutually inclusive and exhaustive EDCs across all of the MDCs. The
exact list of EDCs and which disease goes into which EDC will vary
with both time and circumstances, and will constantly change over
time with changes in medical practice and knowledge. A sample of a
possible set of EDCs for the circulatory system is provided in
table 2.
TABLE-US-00002 TABLE 2 EDCs for the Circulatory MDC Rank Type EDC 1
DC Major Congenital Heart Diseases 2 DC Moderate Congenital Heart
Diseases 3 DC Congestive Heart Failure 4 DC Major Chronic Cardiac
Diseases 5 DC Cardiac Valve Diseases 6 DC History of AMI 7 DC
Angina 8 MC Atrial Fibrillation 9 MC Cardiac Dysrhythmia 10 MC
History of CABG 11 MC History of PTCA 12 MC History of Cardiac
Device 13 MC Coronary Atherosclerosis 14 MC Hypertension 15 C
Ventrical and Atrial Sept Defects 16 C Minor Chronic Cardiac
Diseases CM History of Defibrillator CM Unstable Angina CM Moderate
Hypertension CM Myocardiopathy CM Pulmonary Hypertension CM Graft
Atherosclerosis SA Cyanosis SA Ventricular Tachycardia SA Complete
Heart Block SA Shock SA Cardiac Arrest SA AMI Except Subendocardial
SA Hypotension SA Tachycardia/Palpitation SA Moderate Acute Cardiac
Diseases SA Chest Pain SA Subendocardial AMI SA Minor Hypertension
SA Pediatric CHF MA Atrial Flutter MA Cardiac Inflammation MA Minor
Acute Cardiac Diagnoses MA Malfunction Coronary Bypass Graft MA
Complications CV Device, Implant, Graft MA Malfunction CV Device,
Implant, Graft M Malfunction Vascular Graft
[0051] At step 225 the dominant, moderate and minor chronic EDCs
are ranked hierarchically in terms of their relative contribution
to an individual's need for medical care, debility and death.
Chronic EDCs which result in progressive deterioration of an
individual's health are ranked highest in the chronic EDC
hierarchy. Table 2 contains the EDCs, the disease type and the
chronic EDC rank for the heart and cardiac vascular system MDC.
[0052] Next, a process is defined in step 230 to select from the
EDCs and EPCs the primary chronic disease (PCD) for each organ
system (i.e., MDC), in step 235 a severity of illness (SoI)
leveling matrix is created, and in step 240 SoI levels are defined
for each CRG, resulting in the final classification system in step
245. The PCD, SoI leveling matrix and SoI levels will be discussed
in more detail below.
[0053] After setting initial criteria for the classification
system, the initial criteria preferably are tested against real
data sets to determine their accuracy. For initial testing, one
approach is to Base CRG/SoI assignments on the first year or two of
data, then check how that correlates to expenditures in the third
year of data. Since, in general, individuals with high healthcare
expenditures have significant disease, future expenditures can
stand at least initially as a proxy for the individual's clinical
condition.
[0054] Ultimately, however, detailed reports should be produced
which examine the impact of a wide range of clinical
characteristics on individuals with specific disease and
combinations of diseases. For example, a report might examine the
impact on subsequent expenditures of pneumonia in an individual
with emphysema, over the most recent six months, or having occurred
multiple times. Analysis of these reports then should be fed back
into the different categories and how they are adjusted.
[0055] While steps in creating the classification system have been
defined in a particular order, it will be understood that many of
them can be shuffled. For example, instead of first defining the
MDCs, then sub-dividing them into EDCs, and developing SoI ratings
for the EDCs, it is perfectly possible to first define the EDCs,
then group them into MDCs, and develop the SoI ratings either
before or after the grouping. The important point is that in the
end the classification system has the necessary components, not the
particular order in which they are created.
Phase I:
[0056] Phase I involves applying the various classifications in the
classification system to the medical history of each individual in
a group to define a chronic disease profile and history of past
medical interventions for each individual. To start, refer to FIG.
3, where a classification system 300 (of the type which is the end
result in step 245) is applied to a set of individual data 305 in
step 310 to determine the EDCs and EPCs assigned to the individual,
i.e., the EDCs and EPCs which code for medical care which has been
provided to the patient at some time in the past.
[0057] Once the EDCs and EPCs have been assigned, EDCs and EPCs are
added or deleted in step 315 based on the nature of and the
temporal relationship among the EDCs and EPCs. There are a variety
of ways in which these relationships are expressed. The crucial
distinction is that this is done using clinically based
conditionality which recognizes the interdependence of EDCs and
EPCs. The process design for this step is such as to eliminate the
impact of the order in which the conditions are considered, so as
to ensure consistent results. One preferred way to do this is to
start by creating EDCs, then to adjust for temporal effects and
eliminate EDCs and EPCs which are clinically irrelevant. For
example, as follows: [0058] Create Chronic EDCs from Chronic
Manifestation EDCs: All chronic manifestation EDCs create a chronic
EDC that specifies the underlying chronic disease associated with
the manifestation or acute exacerbation. For example, the diabetic
neuropathy chronic manifestation EDC creates the diabetes EDC.
[0059] Create Chronic EDCs from Multiple Occurrences of an Acute
EDC: Selected acute EDCs that have multiple occurrences over a
period of time create a chronic EDC that indicates the recurrence
of the acute EDC. For example, if the acute EDC for urinary tract
infection occurs at least three times over a period of time that
spans at least 180 days, the chronic EDC for recurrent urinary
tract infection is created. [0060] Significant Acute EDCs Create
Chronic EDCs: Selected significant acute EDCs create a chronic EDC
for the history of the significant acute EDC. For example, the
significant acute EDC for AMI creates a chronic EDC for the history
of the AMI. A history of a significant acute EDC is only created
for significant acute EDCs that indicate a significant progression
of an underlying disease (e.g., CVA) or have long term sequelae
(e.g., hip fracture). The creation of a chronic EDC for the history
of a significant acute EDC is sometimes dependent on the patient's
age. The acute EDC for hip fracture only creates the chronic EDC
for history of hip fracture if the individual is 65 years or older.
[0061] Major Procedure EPCs Create Chronic EDCs: Selected major
procedures that are indicative of advanced disease or have long
term sequelae create a chronic EDC for the history of the major
procedure. For example, the EDC for coronary bypass surgery creates
the chronic EDC for history of coronary bypass surgery. [0062]
Temporal Relationship Between EDCs: If specific EDCs occur prior to
the first occurrence of another specified EDC, the EDC is
eliminated. For example, if the CVA EDC occurs prior to the first
occurrence of the hemiplegia EDC, the CVA EDC is eliminated because
the hemiplegia is a sequelae of the CVA. However, if a CVA occurs
after the first occurrence of hemiplegia, the CVA EDC is not
eliminated since it represents a second CVA. The temporal
relationship between CVA and hemiplegia is the basis for
determining whether there has been a second CVA. [0063] Temporal
Relationship Between EDCs and EPCs: If specific EDCs occur prior to
the occurrence of a specified EPC, the EDC will be eliminated. For
example, if the angina EDC occurred prior to the coronary bypass
EPC, the angina EDC is eliminated because the coronary bypass is
expected to cure the angina. However, if angina occurs after the
coronary bypass EPC, the angina EDC is not eliminated since it
indicates that the coronary bypass was not successful. [0064]
Temporal Relationship Between EPCs: If a specific EPC occurs prior
to the occurrence of another specified EPC, the EPC will be
eliminated. For example, if a dialysis EPC occurs prior to a kidney
transplant EPC, the dialysis EPC is eliminated because the kidney
transplant is expected to eliminate the need for dialysis. However,
if dialysis occurs after the kidney transplant EPC, the dialysis
EPC is not eliminated since it indicates that kidney transplant was
not successful.
[0065] The result of this Phase I analysis at step 320 is a
complete list of EDCs and EPCs which describes each individual's
disease profile and history of past medical interventions.
Phase II:
[0066] In Phase II, the EDC that represents the most significant
chronic disease for which an individual is under active treatment,
referred to as the primary chronic disease (PCD), is identified for
each organ system (i.e., MDC).
[0067] An underlying assumption of the present invention is that
individuals with co-morbid diseases from multiple organ systems
constitute the individuals who have poor outcomes and require
significant medical care. A single disease (i.e., EDC) therefore is
selected from each major organ system (i.e., MDC) for the purpose
of identifying the individuals with co-morbid disease in multiple
organ systems.
[0068] The first step 325 in Phase II is to reduce the number of
chronic EDCs in an MDC that are candidates to be the PCD. Certain
chronic diseases are secondary to (i.e., a by-product of or an
integral part of) another chronic disease. For example, when asthma
and chronic bronchitis are both present, the chronic bronchitis is
secondary to the asthma and the primary disease is asthma. In this
example, chronic bronchitis is not assigned as the PCD if asthma is
present.
[0069] The next step 330 in selecting the PCD is to eliminate from
consideration as the PCD chronic EDCs that are secondary to another
chronic EDC. If only one chronic EDC in an MDC remains after the
chronic EDCs that secondary to another chronic EDC are eliminated,
then that chronic EDC is the PCD for the MDC.
[0070] If more than one chronic EDC remains in the MDC, then the
PCD selection criteria defined in step 230 are used to select the
PCD. Table 3 provides an example of such a set of PCD selection
criteria. In addition to the EDC type, the PCD selection criteria
uses the site of service, recency and duration of treatment to
select the PCD. An underlying assumption to this ranking is that
the diseases that are under recent active treatment have the
greatest impact on the subsequent need for medical care, debility
and death.
TABLE-US-00003 TABLE 3 PCD Selection Criteria Recency of Duration
of EDC Type Site of Service Treatment Treatment Dominant Chronic
Hospital Last Year Dominant Chronic Ambulatory Last Year 90 days
Dominant Chronic Moderate Chronic Hospital Last Year Moderate
Chronic Ambulatory Last Year 90 days
[0071] The selection criteria in Table 3 are applied hierarchically
from top to bottom. The chronic EDC that meets the highest criteria
in the PCD selection hierarchy is selected as the PCD. If more than
one EDC meets a selection criteria then the EDC rank in the MDC is
used to select the EDC to be the PCD.
[0072] Within an EDC type, treatment in a hospital within the most
recent year is highest in the selection hierarchy, followed by
treatment in an ambulatory setting that had a duration of at least
90 days within the most recent year. Based on the PCD selection
criteria, a moderate chronic EDC cannot be selected as the PCD if a
dominant chronic EDC is present, and a minor chronic EDC can not be
selected as the PCD if a moderate chronic EDC is present. However,
within an EDC type, a lower ranking EDC can be selected as the PCD
if it has been under active treatment in the past year.
[0073] At the end of Phase II, a list 335 of a PCD for each MDC
that has at least one chronic EDC present has been determined.
Phase III:
[0074] In Phase III the PCD from each MDC is assigned a severity of
illness level which for brevity, is referred to as the severity
level or SoI. The severity level explicitly describes the extent
and progression of the disease selected as the PCD. A high level of
severity is indicative of poor prognosis, a high degree of
treatment difficulty and a need for substantial medical care in the
future.
[0075] The severity level of a PCD is determined based on the
presence of other EDCs and EPCs. The severity level is primarily
determined by the other chronic and acute EDCs that are present
from the same MDC as the PCD. Chronic EDCs from other MDCs are used
for severity leveling only when the EDC from the other MDC is, with
a high degree of confidence, caused by the PCD. For example,
malabsorption is caused by cystic fibrosis. Thus, the EDC
associated with the malabsorption is used to assign the severity
level for a cystic fibrosis PCD. Although a CVA is more likely to
occur in an individual with diabetes, the diabetes does not cause
the CVA and, therefore, the chronic EDC for history of CVA is not
used to determine the severity level of a diabetes PCD.
[0076] Acute EDCs from any MDC are used to determine the severity
level of the PCD. In particular, acute infections, neurological and
gastrointestinal EDCs are used in the severity leveling as an
indication of the general health status of the individual. The
previous performance of a procedure associated with the treatment
of the PCD is used in severity leveling when the procedure is
indicative of advance disease or has long term sequelae.
[0077] Since any chronic EDC can be a PCD, all chronic EDCs have a
severity leveling matrix, as defined in step 240. The severity
leveling matrix consists of a list of EDCs and EPCs. Along with the
list of EDCs and EPCs are the conditions or rules under which each
EDC and EPC in the list results in a specific severity level. For
example, an individual with a PCD of congestive heart failure who
had been hospitalized with cardiac valve disease in the most recent
year or had been treated at any site for a cardiac valve disease in
the most recent six months is considered to have congestive heart
failure at severity level 4. However, if the individual had cardiac
valve disease, but had not been hospitalized for the cardiac valve
diagnosis during the most recent year nor had been treated at any
site for the cardiac valve disease during the most recent six
months, then the individual is considered to have congestive heart
failure at severity level 3. Thus, the severity level associated
with the cardiac valve disease differs depending on conditions
relating to recency of treatment and the site of treatment.
[0078] In addition to the recency and site of treatment, conditions
used in the severity leveling matrices can relate to the duration
of treatment or the age of the patient. Thus, there is a unique
severity leveling matrix for each chronic EDC.
[0079] As an example, a severity leveling matrix for congestive
heart failure is shown in Table 4. The EDCs at severity level 4 are
primarily acute cardiac events (shock, cardiac arrest, acute
myocardial infarction (AMI), unstable angina and ventricular
tachycardia) that meet the condition of being recent or having
required inpatient care. In addition, severity level 4 includes the
recent occurrence of acute EDCs that are indicative of advanced
congestive heart failure (pleural effusion and hypotension).
Co-morbid cardiac diseases (cardiac valve disease, congenital heart
disease, and major chronic cardiac diseases) that interact with the
congestive heart failure and increase treatment difficulty are also
included at severity level 4. Finally, EDCs and EPCs (tracheostomy)
that relate to the dependence on a respirator are included at
severity level 4.
TABLE-US-00004 TABLE 4 Severity Leveling Matrix For Congestive
Heart Failure Severity Level EPC Type Recency Site Duration 4
Cardiac Valve Diseases DC 2 Years Inpatient 4 Cardiac Valve
Diseases DC 6 Months 4 Moderate Congenital Heart Diseases DC 2
Years 4 Major Congenital Heart Diseases DC 2 Years Inpatient 4
Major Chronic Cardiac Diseases DC 2 Years Inpatient 4 History of
AMI DC 6 Months 4 Unstable Angina CM 1 Year 90 Days 4 Unstable
Angina CM 1 Year Inpatient 4 Pleural Effusion SA 1 Year 4
Hypotension SA 6 Months 4 Shock SA 1 Year 4 Cardiac Arrest SA 1
Year 4 Ventricular Tachycardia SA 6 Months 4 Ventricular
Tachycardia SA 1 Year Inpatient 4 Dependence on Respirator MA 1
Year 4 Permanent Tracheostomy EPC 2 Years 4 Temporary Tracheostomy
EPC 2 Years 3 Cardiac Valve Diseases DC 2 Years 3 Major Congenital
Heart DC 2 Years 3 Major Chronic Cardiac Diseases DC 2 Years 3
History of AMI DC 2 Years 3 Atrial Fibrillation MC 2 Years 90 Days
3 History of PTCA MC 2 Years 3 Cardiac Dysrhythmia MC 2 Years 90
Days 3 Cardiac Dysrhythmia MC 6 Months 3 Coronary Atherosclerosis
MC 6 Months 3 Unstable Angina CM 1 Year 3 History of Defibrillator
CM 2 Years 3 Graft Atherosclerosis CM 2 Year 3 Convulsions SA 1
Year 90 Days 3 Moderate Neurological SSFs SA 1 Year 90 Days 3
Extreme Neurological SSFs SA 1 Year 90 Days 3 Pulmonary Emboli SA 1
Year 3 Subendocardial AMI SA 1 Year 3 Thrombophlebitis SA 1 Year 90
Days 3 AMI Except Subendocardial SA 1 Year 3 Moderate Acute Cardiac
Diseases SA 6 Months 3 Complete Heart Block SA 1 Year 3 Nausea,
Vomiting & Diarrhea SA 1 Year 90 Days 3 Malfunction Coronary
Bypass Graft MA 1 Year 3 Wheelchair MA 1 Year 3 Metabolic/Endocrine
Diseases MA 6 Months 3 Mechanical Ventilation EPC 2 Years 3
Respiratory Therapy EPC 2 Years 90 Days 3 Hospital Bed EPC 2 Years
3 Wheelchair (Motorized) EPC 2 Years 2 Angina DC 2 Years 2 History
of CABG MC 2 Years 2 Atrial Fibrillation MC 2 Years 2 Minor Chronic
Artery & Vein C 1 Year 90 Days Diseases 2 Obesity CM 2 Years 2
Moderate Neurological SSFs SA 1 Year 2 Extreme Acute Neurological
SA 1 Year Diseases 2 Chest Pain SA 1 Year 90 Days 2 Hypotension SA
1 Year Inpatient 2 Significant GI Diagnoses SA 1 Year 2 Minor Acute
GI Diagnoses SA 1 Year 2 Acute Pancreatitis SA 1 Year 2 Hypovolemia
SA 1 Year Inpatient 2 Cellulitis SA 1 Year 90 Days 2 Major
Infections SA 6 Months 2 Major Acute Mental Health Diseases SA 6
Months 2 High Mortality Acute Diseases SA 1 Year 2 Cardiac
Inflammation MA 1 Year Inpatient 2 Atrial Flutter MA 1 Year 2 Acute
Skin Diagnoses MA 1 Year 90 Days 2 Minor Bacterial Infections MA 1
Year 90 Days 2 Minor Infection MA 6 Months 2 Coronary Bypass EPC 2
Years 2 Major Cardiac Procedure EPC 2 Years 2 Permanent Cardiac
Pacemaker EPC 2 Years 2 Oxygen Therapy EPC 2 Years 2 Walkers EPC 2
Years 2 Commode EPC 2 Years 2 Wheelchair (Standard) EPC 2 Years 1
Hypertension MC 2 Years 1 Cardiac Dysrhythmia MC 2 Years 1 History
of Cardiac Device MC 2 Years 1 Coronary Atherosclerosis MC 2 Years
1 Ventrical and Atrial Sept Defects C 1 Year 1 Minor Chronic
Cardiac Diseases C 1 Year 1 Chest Pain SA 1 Year 1 Cyanosis SA 1
Year 1 Minor Hypertension SA 1 Year 1 Pediatric CHF SA 1 Year 1
Tachycardia/Palpitation SA 1 Year 1 Moderate Acute Cardiac Diseases
SA 1 Year 1 Malfunction CV Device, Implant, MA 1 Year Graft 1 Minor
Acute Cardiac Diseases MA 1 Year 1 Complications CV Device,
Implant, MA 1 Year Graft 1 Cardiac Inflammation MA 1 Year 1
Malfunction Vascular Graft M 1 Year
[0080] Severity level 3 for congestive heart failure includes some
of the same EDCs as level 4 (AMI, unstable angina, major chronic
cardiac disease and congenital heart disease) but without the
conditions of being recent or requiring inpatient care. Other
moderate cardiac or circulatory EDCs are included at severity level
3 (complete heart block, cardiac dysrhythmia, thrombophlebitis,
atrial fibrillation, coronary atherosclerosis, pulmonary emboli,
history of coronary bypass and history of defibrillator). Recent
acute endocrine, metabolic and neurological problems are also
included at severity level 3 since they can be associated with
advanced congestive heart failure. Finally, the presence of EPCs
that are indicative of significant debility such as a hospital bed
for the home or the need for a motorized wheelchair are included at
severity level 3.
[0081] Severity level 2 for congestive heart failure includes some
acute cardiac EDCs (chest pain, atrial flutter, stable angina and
cardiac inflammation) plus some of the moderate cardiac or
circulatory EDCs from severity level 3 (e.g., atrial fibrillation
without the condition of having a duration of at least 90 days).
Severity level 2 also includes a wide range of acute problems from
other MDCs (e.g., infections, mental health diagnoses, skin
diagnoses, etc.) that are indicative of general health status.
Finally, an extended list of history of significant cardiac
procedures (e.g., cardiac pacemaker) and EPCs related to medical
supplies that are indicative of debility (e.g., walker, commode)
are included at severity level 2.
[0082] If none of the EDCs and EPCs and associated conditions in
severity levels 2 through 4 are present, then the congestive heart
failure PCD is assigned severity level 1. For completeness, all the
EDCs in the heart and cardiac vascular MDC that are not used in
severity levels 2 through 4 are included in level 1 in the severity
leveling matrix for congestive heart failure. However, since
severity level 1 is the default severity level, a severity of level
1 can be assigned without any of the EDCs listed in level 1 being
present.
[0083] The number of severity levels specified in the severity
leveling matrix may vary across EDCs. Minor chronic EDCs and
non-metastatic malignancy EDCs have only two severity levels
specified because of the limited clinical spectrum of these
diseases. All dominant chronic, moderate chronic and metastatic
malignancy EDCs have four severity levels.
[0084] The severity level for a PCD is determined based on the
following steps: [0085] 1. In step 340, use the complete list 320
of EDCs and EPCs created in Phase Ito identify the subset of EDCs
and EPCs that are present in the severity leveling matrix for the
PCD. [0086] 2. In step 345, for each EDC and EPC identified in step
340, evaluate the associated conditions in the severity leveling
matrix and determine the severity level for each EDC and EPC.
[0087] 3. In step 350, set the severity level for the PCD equal to
the highest severity level associated with any of the EDC and EPCs
from step 345.
[0088] Since the same EDCs and EPCs can be used in the severity
leveling matrix for PCDs in more than one MDC, it is possible that
the same EDC or EPC could determine the severity level for more
than one PCD. Thus, the presence of a single EDC or EPC could have
a disproportionate impact on the overall severity level of the
individual. To avoid this possibility, the severity level for each
PCD preferably is determined in step 345 with the constraint that
no EDC or EPC can determine the severity level (i.e., be the EDC or
EPC used in step 3) of more than one PCD.
[0089] At the end of Phase III in step 355, all PCDs for an
individual have been assigned a severity level.
Phase IV:
[0090] In phase IV, the PCD/SoI information is used to identify the
CRG Status, Base CRG, and overall SoI. The CRG Status indicates a
general overall status for the individual (e.g., anything from
catastrophic to healthy). The Base CRG indicates the primary cause
for the CRG status (e.g., Heart And Cardiac Vascular Diseases),
while the overall SoI correlates to the severity of the Base CRG
(e.g., in the hospital, ambulatory) [0091] The individual is
assigned to one of a number of CRG Statuses in step 360 based on
the PCDs that are present. A preferred embodiment has 9 CRG
Statuses: [0092] Catastrophic Conditions: Catastrophic conditions
include long term dependency on a medical technology (e.g.,
dialysis, respirator, TPN) and life-defining chronic diseases that
dominate the medical care required (e.g., persistent vegetative
state, cystic fibrosis, AIDS, history of heart transplant). [0093]
Dominant and Metastatic Malignancies: A malignancy that dominates
the medical care required (e.g., brain malignancy) or a non
dominant malignancy (e.g., prostate malignancy) that is metastatic.
[0094] Dominant Chronic Disease in Three or More Organ Systems:
Dominant chronic disease in three or more organ systems is
identified by the presence of three or more dominant PCDs. [0095]
Significant Chronic Disease in Multiple Organ Systems: Significant
chronic diseases in multiple organ systems is identified by the
presence of two or more PCDs of which at least one is a dominant or
moderate PCD. PCDs that are a severity level 1 minor chronic
disease are not considered a significant chronic disease and are
not used to identify the presence of significant chronic disease in
multiple organ systems. [0096] Single Dominant or Moderate Chronic
Disease: Single dominant or moderate is identified by the presence
of a single dominant or moderate PCD. [0097] Minor Chronic Disease
in Multiple Organ Systems: Minor chronic disease in multiple organ
systems is identified by the presence of two or more minor PCDs.
[0098] Single Minor Chronic Disease: A single minor chronic disease
is identified by the presence of a single minor PCD. [0099] History
of Significant Acute Disease: A history of significant acute
disease is identified by the presence of one or more significant
acute EDCs in the last six months with no PCDs present. [0100]
Healthy: A healthy status is identified by the absence of any PCDs
or recent significant acute EDCs or EPCs.
[0101] The CRG Status is assigned hierarchically starting with the
catastrophic status. The first status in the hierarchy for which
the status criteria are met is assigned as the CRG Status.
[0102] Once the CRG Status is determined, the Base CRG and overall
severity level of the individual is determined in step 365. The
Base CRG is assigned based on the PCD(s) which are present in the
individual's record. The SoI in turn depends on the severity level
of those PCDs, and where appropriate, any adjustments applied to
the CRG status and Base CRG.
[0103] Catastrophic Conditions: The first status in the CRG status
hierarchy is for individuals with catastrophic conditions
associated with long term dependence on medical technology or
life-defining chronic diseases that dominate the medical care
required. All conditions that are considered catastrophic are
ordered hierarchically (e.g., dialysis is higher in the
catastrophic hierarchy than history of heart transplant). If there
is more than one catastrophic condition present, the catastrophic
condition that is highest in the catastrophic hierarchy is assigned
as the Base CRG.
[0104] For each catastrophic condition there is a four level
severity leveling matrix (defined in step 240) that is specific to
the catastrophic condition. In addition, since individuals with a
catastrophic condition can also have diseases in organ systems that
are not directly related to the catastrophic condition, the
severity level that is assigned based on the severity leveling
matrix specific to the catastrophic condition is adjusted based on
the presence of PCDs from organ systems unrelated to the
catastrophic condition. The additional adjustment to the severity
level is done to insure that the severity level of the catastrophic
condition fully reflects to the total burden of illness.
[0105] Dominant And Metastatic Malignancies: The second status in
the CRG status hierarchy is for individuals with dominant or
metastatic malignancies. Certain malignancies (e.g., brain,
pancreas, etc.) are similar to catastrophic conditions in that they
are life defining and dominate the medical care required. Other
malignancies (e.g., prostate, colon, etc.) do not dominate the
medical care required unless they are metastatic. When multiple
malignancies are present, each malignancy is classified as primary
or secondary (e.g., a bone malignancy is considered secondary to a
prostate malignancy). A primary malignancy is considered metastatic
if there is a related secondary malignancy present.
[0106] In addition to identifying a primary metastatic malignancy
by the presence of a related secondary malignancy, there are also
some conditions that are indicative of an advanced stage of the
primary malignancy and are, for all practical purposes, indicative
of metastasis (e.g., malnutrition, the need for a second course of
chemotherapy, etc.). For each dominant or metastatic primary
malignancy there is a four level severity leveling matrix that is
specific to the primary malignancy. In addition, since individuals
with a dominant or metastatic primary malignancy can also have
diseases in organ systems that are not directly related to the
primary malignancy, the severity level that is assigned based on
the severity leveling matrix specific to the primary malignancy is
adjusted based on the presence of PCDs from organ systems unrelated
to the primary malignancy. The additional adjustment to the
severity level is done to insure that the severity level of the
dominant or metastatic primary malignancy fully reflects the total
burden of illness. Primary malignancies that are not dominant or
metastatic are treated like any other disease and are included in
the subsequent portions of the CRG status hierarchy.
[0107] Dominant Chronic Disease In Three Or More Organ Systems: The
third status in the CRG status hierarchy is for individuals with
dominant chronic diseases in three or more organ systems. Explicit
combinations of three dominant PCDs are identified (e.g.,
congestive heart failure, diabetes and emphysema). The explicit
combinations of three dominant PCDs are ranked hierarchically.
Individuals with three or more dominant PCDs are assigned to a Base
CRG that corresponds to the first match in the hierarchy. If the
dominant PCDs do not match any of the explicit combinations, then
the individual is assigned to a residual Base CRG that corresponds
to any combination of three dominant PCDs that are not explicitly
specified in the hierarchy.
[0108] Each Base CRG that is comprised of three or more dominant
PCDs is subdivided in six severity levels. The severity level is
determined using the severity level for each of the PCDs that
comprised the CRG. Table 5 provides an example of a suitable matrix
to assign the severity of illness.
TABLE-US-00005 TABLE 5 Severity Levels for CRGs Composed of Three
or More Dominant PCDs CRG Severity Severity Level of PCDs Level 4 3
2 or 1 6 3 or more 5 2 1 or more 4 2 None 1 or more 4 1 2 or more 3
1 1 1 or more 3 1 None 2 or more 3 1 3 or more 2 2 1 or more 2 1 2
or more 1 1 3
[0109] The criteria in Table 5 are applied hierarchically from top
to bottom. The severity level for the CRG is assigned based on the
first criteria that is matched in Table 5. For example, if the
three dominant PCDs that comprise the CRG have severity levels of
4,4 and 2, then the severity level of the CRG would be 4. The
severity level that results from Table 5 is generic to all CRGs,
since the same Table 5 applies to all CRGs that are comprised of
three more dominant PCDs.
[0110] The CRG severity level that results from the application of
the generic criteria in Table 5 is then adjusted based on criteria
that is specific to that Base CRG. The adjustments reflect that
conditions become more complex in the presence of multiple disease
processes, or the presence of other complication factors. For
example, the generic severity level for the Base CRG comprised of
congestive heart failure, diabetes and emphysema is increased by
one if the EDC for unstable angina is present and the unstable
angina has been actively treated in the most recent six month
period. The unstable angina is often treated by performing coronary
bypass surgery. However, if the patient also has diabetes and
emphysema the surgical treatment may not be an option resulting in
a difficult to treat patient with a probable poor prognosis.
[0111] Significant Chronic Disease In Multiple Organ Systems: The
fourth status in the CRG status hierarchy is for individuals with
significant chronic diseases in multiple organ systems. For
individuals who do not have three or more dominant chronic diseases
but do have multiple chronic diseases with at least one dominant or
moderate chronic disease, explicit combinations of two PCDs are
identified (e.g., congestive heart failure and diabetes). Severity
level 1 minor PCDs are not used in identifying combinations of two
significant chronic diseases since they have minimal impact on the
individual's need for medical care.
[0112] The explicit combinations of two PCDs are ranked
hierarchically. Individuals with two or more PCDs are assigned to a
Base CRG that correspond to the first match in the hierarchy. If
the PCDs do not match any of the explicit combinations, then a
residual Base CRG is assigned that correspond to any combination of
two PCDs that are not explicitly specified in the hierarchy.
[0113] Each Base CRG that is comprised of two PCDs is subdivided
into between 2 and 6 severity levels. Since non-metastatic
malignancy PCDs only have two severity levels and since minor PCDs
at severity level 1 are not used in the combinations of two PCDs,
the number of severity levels depend on the PCDs that comprise the
combination. A combination that is comprised of a non-metastatic
malignancy PCD and a severity level 2 minor PCD has two severity
levels. A combination that is comprised of a dominant or moderate
PCD and a severity level 2 minor PCD or a non-metastatic malignancy
PCD has four severity levels. All other combinations of PCDs have
six severity levels.
[0114] The severity levels for the CRG is determined using the
severity level for each of the PCDs that comprise the combination.
Since the individual PCDs that comprise the combination can be very
different in terms of relative clinical significance (e.g., the
combination of congestive heart failure and diabetes versus the
combination of congestive heart failure and glaucoma) the criteria
used to determine the severity level for the CRG is specific to the
PCDs that comprise the combination. Table 6 shows the severity
levels for a CRG composed of the dominant PCD for diabetes and the
dominant PCD for congestive heart failure.
TABLE-US-00006 TABLE 6 Severity Levels for the CRG that is
Comprised of the PCDs for Congestive Heart Failure and Diabetes
Diabetes Severity Congestive Heart Failure Level Severity Level 4 3
2 1 4 6 5 4 4 3 5 4 3 3 2 4 3 2 2 1 3 2 2 1
[0115] Based on the criteria in Table 6, if the diabetes PCD is
severity level 3 and the congestive heart failure PCD is severity
level 4, the severity level for the CRG is 5.
[0116] The CRG severity level that results from the application of
criteria like that in Table 6 is further adjusted based on criteria
that is specific to that Base CRG. The adjustments reflect that
conditions become more complex in the presence of multiple disease
process, or the presence of other complication factors. For
example, the CRG severity level for the Base CRG comprised of
congestive heart failure and diabetes is increased by one if the
PCD for chronic gastric ulcer is present and the chronic gastric
ulcer has been actively treated in the most recent six month
period. Since the gastric ulcer PCD is not a dominant chronic
disease the individual is not assigned to one of the CRGs for three
dominant chronic diseases. However, the chronic ulcer disease
complicates the treatment of the congestive heart failure and
diabetes and, therefore, increases the severity level.
[0117] Single Dominant Or Moderate Chronic Disease: The fifth
status in the CRG status hierarchy is for individuals with a single
dominant or moderate chronic disease. These individuals have only
one PCD. The Base CRG is the same as the PCD (i.e., if the single
PCD for the patient is diabetes, the Base CRG is diabetes). The
severity level for the CRG is the same as the PCD severity level.
The malignancy PCDs have two severity levels and all other moderate
and dominant PCDs have four severity levels.
[0118] Minor Chronic Disease In Multiple Organ Systems: The sixth
status in the CRG status hierarchy is for individuals with two or
more minor chronic diseases. Individuals with two or more minor
chronic diseases are assigned to a single Base CRG which has four
severity levels based on the number of minor chronic PCDs present
and the severity level of the minor chronic PCDs.
[0119] Single Minor Chronic Disease: The seventh status in the CRG
status hierarchy is for individuals with a single minor chronic
disease. These individuals have only one PCD. The Base CRG is the
same as the PCD. The severity level for the CRG is the same as the
PCD severity level.
[0120] History Of Significant Acute Disease: The eighth status in
the CRG status hierarchy is for individuals with a history of
significant acute disease. The individual has no PCDs present but
at least one significant acute EDC is present. If the significant
acute EDC (e.g., AMI) creates a chronic EDC for the history of the
significant acute (e.g., history of AMI) then the individual would
have a PCD present and, therefore, would not be assigned to the
status for history of significant acute disease. Thus, individuals
with significant acute diseases with significant sequelae such as
AMI are not included in this status. However, the significant acute
diseases that are present in this status can be a precursor to
chronic disease or place the individual at risk for the development
of chronic disease (e.g., chest pain). Thus, although the patients
in the history of significant acute disease status do not have any
chronic diseases, they are distinct from healthy individuals.
[0121] Certain EPCs are also considered equivalent to a significant
acute disease. For example, if the skin graft EPC is present, the
individual is assigned to the history of significant acute disease
status even if no significant acute EDCs are present. The
performance of a skin graft is considered indicative of a history
of significant acute disease. There are a number of Base CRGs,
e.g., six, for individuals with history of significant acute
disease. The Base CRGs are determined based on the number and
duration of the significant acute diseases present. There are no
severity levels assigned to the history of significant acute
disease CRGs.
[0122] Healthy: The ninth and final status in the CRG status
hierarchy is for healthy individuals who have no PCDs and no
significant acute EDCs or EPCs. They may have minor acute EDCs
present (e.g., common cold) but are otherwise healthy. There is a
single CRG for healthy individuals.
[0123] The end result of phase IV is a CRG/SoI for the individual,
at 370. Individual CRG/SoI data can be used for a variety of
purposes, most notably as a very shorthand description of the
overall health condition of the individual, but are most useful
when analyzed in groups, in phase V.
Phase V:
[0124] For higher level reports, it is useful to aggregate the CRG
levels into smaller sets of risk groups. In step 410, the starting
point for this is the CRG/SoIs developed for a an individual in
phases Ito IV. Phase V then consolidates the CRGs into successive
tiers of aggregation, preferably three tiers. Each successive tier
of aggregation has fewer Base CRGs. Across the CRG aggregations,
the CRG Status and the severity levels within the aggregated CRGs
are maintained. Thus, the successive tiers of CRG aggregation
maintain the CRG Status and maintain the severity levels but reduce
the number of Base CRGs.
[0125] Although the aggregation of CRGs reduces clinical precision,
the successive tiers of aggregation maintain clinical
meaningfulness (in contrast to past practices focussing just on
cost). The successive tiers of aggregation take into consideration
the future medical care needs and clinical similarity of the
individuals assigned to the aggregated CRGs. The aggregated CRGs
are referred to as ACRGs and the successive tiers of aggregation
may be referred to with suitable designators, e.g., ACRG1, ACRG2
and ACRG3, with ACRG3 being the highest level of aggregation. Table
7 provides an example of summarizes the aggregation of CRGs into
ACRGs.
TABLE-US-00007 TABLE 7 Aggregation of CRGs into ACRGs CRG Status
CRG ACRG1 ACRG2 ACRG3 Catastrophic Base 11 10 6 1 SoI Levels 4 4 4
6 Total 44 40 24 6 Dominant and Metastatic Malignancies Base 23 3 1
1 SoI Levels 4 4 5 4 Total 92 12 5 4 Dominant Chronic Disease in
Three or More Organ Systems Base 21 7 2 1 SoI Levels 6 6 6 6 Total
126 42 12 6 Significant Chronic Disease in Multiple Organ Systems
Base 61 24 8 1 SoI Levels 2, 4, 6 4, 6 5, 6 6 Total 324 134 47 6
Single Dominant or Moderate Chronic Disease Base 109 25 8 1 SoI
Levels 2, 4 2, 4 2, 5, 6 6 Total 406 96 35 6 Minor Chronic Disease
in Multiple Organ Systems Base 1 1 1 1 SoI Levels 4 2 2 2 Total 4 2
2 2 Single Minor Chronic Diseases Base 40 21 2 1 SoI Levels 2 2 2 2
Total 80 42 4 2 History of Significant Acute Disease Base 6 1 1 1
SoI Levels 1 1 1 1 Total 6 1 1 1 Healthy Base 1 1 1 1 SoI Levels 1
1 1 1 Total 1 1 1 1 Total Base 273 93 30 9 SoI Levels 1, 2, 4, 6 1,
2, 4, 6 1, 2, 4, 5, 6 1, 2, 5, 6 Total 1083 370 131 34
[0126] In the example used in Table 7, the number of Base CRGs are
273, 93, 30 and 9 and the number of CRGs with severity levels are
1083, 370, 131 and 34 for CRG, ACRG1, ACRG2 and ACRG3,
respectively.
[0127] The process of aggregating CRGs into successive tiers of
ACRGs is illustrated in Table 8 for the CRG Status comprising
dominant and moderate chronic diseases for the MDCs for heart and
coronary vascular diseases, peripheral vascular and non-cardiac
vascular diseases and respiratory diseases.
TABLE-US-00008 TABLE 8 Aggregation of Cardiopulmonary CRGs into
ACRGs for the CRG Status Consisting of a Single Dominant or
Moderate Disease CRGs Heart and Coronary Vascular Diseases 13 Base
CRGs .times. 4 SoI Levels = 54 CRGs DC Congestive Heart Failure DC
Major Congenital Heart DC Moderate Congenital Heart DC Major
Cardiac Diagnoses DC Cardiac Valve Diagnoses DC History of AMI DC
Angina MC Atrial Fibrillation MC Cardiac Dysrhythmia MC History of
CABG MC History of PTCA MC History of Cardiac Device MC Coronary
Atherosclerosis MC Hypertension Peripheral and Non Cardiac Vascular
Diseases 3 Base CRGs .times. 4 SoI Levels = 12 CRGs DC Peripheral
Vascular Disease DC Moderate Artery and Vein Disease MC Leg
Varicosities with Ulcer Respiratory Diseases 5 Base CRGs .times. 4
SoI Levels = 20 CRGs DC COPD and Bronchiectasis DC BPD/Major Lung
Anomaly DC Significant Pulmonary Disease DC Tracheostomy Status MC
Asthma ACRG1 Circulatory Diseases 4 Base ACRG1s .times. 4 SoI
Levels = 16 ACRG1s Congestive Heart Failure DC Congestive Heart
Failure Dominant chronic circulatory diseases except CHF DC Major
Congenital Heart DC Moderate Congenital Heart DC Major Cardiac
Diagnoses DC Cardiac Valve Diagnoses DC History of AMI DC Angina DC
Peripheral Vascular Disease DC Moderate Artery and Vein Disease
Moderate chronic circulatory diseases except hypertension MC Atrial
Fibrillation MC Cardiac Dysrhythmia MC History of CABG MC History
of PTCA MC History of Cardiac Device MC Coronary Atherosclerosis MC
Leg Varicosities with Ulcer Hypertension MC Hypertension
Respiratory Diseases 2 Base ACRG1s .times. 4 SoI Levels = 8 ACRG1s
Dominant chronic respiratory diseases DC COPD and Bronchiectasis DC
BPD/Major Lung Anomaly DC Significant Pulmonary Disease DC
Tracheostomy Status Asthma MC Asthma ACRG2 Cardiopulmonary Diseases
1 Base ACRG2 .times. 6 SoI Levels = 6 ACRG2s DC Congestive Heart
Failure DC Major Congenital Heart DC Moderate Congenital Heart DC
Major Cardiac Diagnoses DC Cardiac Valve Diagnoses DC History of
AMI DC Angina DC Peripheral Vascular Disease DC Moderate Artery and
Vein Disease DC COPD and Bronchiectasis DC BPD/Major Lung Anomaly
DC Significant Pulmonary Disease DC Tracheostomy Status MC Atrial
Fibrillation MC Cardiac Dysrhythmia MC History of CABG MC History
of PTCA MC History of Cardiac Device MC Coronary Atherosclerosis MC
Leg Varicosities with Ulcer MC Hypertension MC Asthma
[0128] As shown in Table 8, in these three MDCs there are 24 Base
CRGs, each with 4 severity levels for a total of 96 CRGs. In step
415, the CRGs are aggregated into ACRG1s by combining the MDCs for
heart and coronary vascular disease together with the MDC for
peripheral vascular and non-cardiac vascular disease into
"circulatory diseases", which is subdivided into the following four
circulatory base ACRG1s. [0129] Congestive heart failure [0130]
Dominant chronic circulatory diseases except CHF [0131] Moderate
chronic circulatory diseases except hypertension [0132]
Hypertension Similarly, the CRGs in the respiratory system are
aggregated into two base ACRG1s [0133] Dominant chronic respiratory
diseases [0134] Asthma Thus, the 24 Base CRGs from these three MDCs
are consolidated into six base ACRG1s.
[0135] The severity level for the ACRG1 is determined in step 420.
It is the same as the severity level for the CRG (e.g., if the
severity for the angina CRG is level 3, the severity level for the
ACRG1 for dominant chronic circulatory diseases except CHF is also
level 3). Thus, the 96 CRGs in these three MDCs for the single
dominant or moderate chronic disease status are aggregated into 24
ACRG1s.
[0136] In step 425, the six Base CRGs in ACRG1 are aggregated into
a single ACRG2 for cardiopulmonary disease. However, because there
is significant clinical diversity across the six ACRG1s, the number
of severity levels in ACRG2 is expanded to six. The mapping of the
four severity levels for the ACRG1s to the six severity levels for
the ACRG2s is shown in Table 9.
TABLE-US-00009 TABLE 9 Mapping of ACRG1 Seventy Level to ACRG2
Seventy Level for Cardiopulmonary Diseases ACRG2 severity Level
Base ACRG1 1 2 3 4 5 6 Congestive Heart Failure 1 2 3 4 Dominant
Chronic Circulatory System 1 2 3 4 Diseases except CHF Dominant
Chronic Respiratory Diseases 1 2 3 4 Moderate Chronic Circulatory
System 1 2 3 4 Diseases except Hypertension Hypertension 1 2 3 4
Asthma 1 2 3 4
[0137] Severity level 6 for cardiopulmonary base ACRG2 is composed
of ACRG1 severity level 4 congestive heart failure and ACRG1
severity level 4 dominant chronic respiratory diseases. The mapping
of the ACRG1 severity levels to the ACRG2 severity levels in step
430 reflects both the ACRG1 severity level and the relative
clinical significance of the different base ACRG1s that are
aggregated into a single base ACRG2.
[0138] In step 430, all base ACRG2s in the single dominant or
moderate chronic disease status are aggregated into a single base
ACRG3 with six severity levels. Similar to the severity level
mapping between ACRG1 and ACRG2, in step 440, there is a severity
level mapping between ACRG2 and ACRG3 that reflects the relative
clinical significance of the different base ACRG2s that are
aggregated into the single base ACRG3. The end result in step 445
is a set of ACRG/SoI ratings for the individuals using ever smaller
sets of Base CRG categories.
[0139] The clinical logic in the five phase process for determining
CRG assignment results in a severity adjusted set of mutually
exclusive and exhaustive categories that differentiate the relative
need for medical care as well as debility and death. The multiple
aggregations of CRGs provide the flexibility for CRG to be used at
a level of detail that corresponds to the needs of all users
including payers and providers. Since the successive consolidations
of CRGs are formed in a hierarchical manner, upper management can
receive highly aggregated reports, while clinicians can receive a
corresponding set of reports that contain more details.
[0140] The CRGs can be used in several ways to project future
costs, by computing the average future cost of individuals assigned
to each CRG, and weighting total costs for a group based on the
number of individuals in each CRG. For example, suppose two years
of historical data were available. CRGs would be assigned based on
the demographic and clinical information in the first year. CRG
payment weights would be computed as the average expenditures in
the second year for individuals assigned to each CRG based on the
first year data. Thus, the first year of data is used to assign the
CRG and the second year is used to compute the CRG payment weight.
The separation of the CRG clinical model and the CRG payment
weights allows payers to compute their own payment weights while
using the standard CRG clinical model.
[0141] The CRGs also are very useful in projecting costs for
different mixes of coverage. The specific categories of
expenditures included in capitated payment arrangements can vary.
For example, pharmacy costs may be carved out of the capitated
rate. The CRG payment weights can be expressed in terms of the cost
components that make up the payment weight (e.g., pharmacy,
physician, hospital, laboratory, etc.) so that the proportion of
the payment weight that is associated with each cost component is
known. For example, a capitated payment arrangement negotiated with
a managed care organization might exclude pharmacy expenditures,
which could be paid on a capitated basis to a separate
organization. CRG payment weights excluding pharmacy and separate
CRG pharmacy payment weights can be generated to support such a
payment arrangement. The separation of the clinical model and
payment weights, and the relatively straight-forward method for
computing the CRG payment weights (i.e., the average values for
each CRG) provides great flexibility in establishing capitated
payment arrangements.
[0142] The multiple levels of aggregated CRGs also make the CRGs
useful in calculating payment weights for relatively small groups.
Payers that wish to compute their own payment weights but have
relatively few covered individuals can use a highly consolidated
tier of CRG aggregation in order to have a sufficient number of
covered individuals in each ACRG to compute a payment weight.
[0143] It will be understood that these exemplary embodiments in no
way limit the scope of the invention. Other modifications of the
invention will be apparent to those skilled in the art in view of
the foregoing description. These descriptions are intended to
provide specific examples of embodiments which clearly disclose the
present invention. Accordingly, the invention is not limited to the
described embodiments or to the use of specific elements,
dimensions, materials or configurations contained therein. All
alternative modifications and variations of the present invention
which fall within the spirit and scope of the appended claims are
covered.
* * * * *