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Cited by 1,757Chronic Disease Management StrategiesHealth Systems, Economic Evaluations, Quality of LifeStatistical Methods in Epidemiology

How to measure comorbiditya critical review of available methods

Open access
DEGROOT, V, BECKERMAN, H, LANKHORST, G, BOUTER, L·2003·Journal of Clinical Epidemiology
DOI 10.1016/s0895-4356(02)00585-1
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Abstract

The object of this article was to systematically review available methods to measure comorbidity and to assess their validity and reliability. A search was made in Medline and Embase, with the keywords comorbidity and multi-morbidity, to identify articles in which a method to measure comorbidity was described. The references of these articles were also checked, and using a standardized checklist the relevant data were extracted from these articles. An assessment was made of the content, concurrent, predictive and construct validity, and the reliability. Thirteen different methods to measure comorbidity were identified: one disease count and 12 indexes. Data on content and predictive validity were available for all measures, while data on construct validity were available for nine methods, data on concurrent validity, and interrater reliability for eight methods, and data on intrarater reliability for three methods. The Charlson Index is the most extensively studied comorbidity index for predicting mortality. The Cumulative Illness Rating Scale (CIRS) addresses all relevant body systems without using specific diagnoses. The Index of Coexisting Disease (ICED) has a two-dimensional structure, measuring disease severity and disability, which can be useful when mortality and disability are the outcomes of interest. The Kaplan Index was specifically developed for use in diabetes research. The Charlson Index, the CIRS, the ICED and the Kaplan Index are valid and reliable methods to measure comorbidity that can be used in clinical research. For the other indexes, insufficient data on the clinimetric properties are available.

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  • The modified Charlson Comorbidity Index is a valid measure of comorbidity.

    “modified Charlson Comorbidity Index [19,20]”

    From Income disparity and utilization of cardiovascular preventive care services among U.S. adults (2021) · cites this paper as [20]

    The Results report evidence for the Charlson Index’s validity and describe several adaptations; the Discussion concludes that the Charlson Index is a valid measure of comorbidity. Our copy does not identify which modification the citing document used or separately establish that version’s validity. (LLM, conf=0.83)

    Experimental — accuracy not yet measured

  • The Charlson comorbidity index is the most extensively studied comorbidity index and is considered a valid and reliable method to measure comorbidity in clinical research.

    “The Charlson comorbidity index is the most extensively studied comorbidity index and is considered a valid and reliable method to measure comorbidity that can be used in clinical research [6,14].”

    From ESPEN guideline on nutritional support for polymorbid medical inpatients (2023) · cites this paper as [14]

  • The sequential model has been found to entail significant benefits in terms of relapse rate.

    “Such an approach has been found to entail significant benefits in terms of relapse rate [50].”

    From The Deceptive Manifestations of Treatment Resistance in Depression: A New Look at the Problem (2020) · cites this paper as [50]

  • In unipolar depression, sequential use of pharmacotherapy and psychotherapy improves long-term outcome after treatment termination.

    “In unipolar depression, the sequential use of pharmacotherapy and psychotherapy was found to improve long-term outcome after termination of treatment [50].”

    From The Deceptive Manifestations of Treatment Resistance in Depression: A New Look at the Problem (2020) · cites this paper as [50]

  • The sequential model of treatment was developed to address complexities and unsatisfactory remission from current therapeutic strategies.

    “For addressing such complexities and the unsatisfactory degree of remission that current therapeutic strategies entail [19], the sequential model of treatment has been developed [49, 50].”

    From The Deceptive Manifestations of Treatment Resistance in Depression: A New Look at the Problem (2020) · cites this paper as [50]

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Research works printed but not linked: 1

  1. Iezzoni LI, Ash AS, Coffman GA, Moskowitz MA. Predicting in- hospital mortality. A comparison of severity measurement ap- proaches. Med Care 1992;30:347-59.

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Authors
DEGROOT, V, BECKERMAN, H., LANKHORST, G., & BOUTER, L.
Affiliations
Amsterdam UMC Location Vrije Universiteit Amsterdam (NL)
Corresponding author
DEGROOT, V
ORCID
Venue
Journal of Clinical Epidemiology
Publisher
Elsevier BV
Published
2003-03
Volume
56
Issue
3
Pages
221-229
ISSN
0895-4356 (ISSN-L)
DOI
10.1016/s0895-4356(02)00585-1
OpenAlex
W2140452679
Cited by
1,757
References
70
Citations by year
2026: 33 · 2025: 42 · 2024: 87 · 2023: 83 · 2022: 77 · 2021: 87 · 2020: 108 · 2019: 102 · 2018: 89 · 2017: 84 · 2016: 88 · 2015: 95 · 2014: 117 · 2013: 85 · 2012: 103
FWCI
4.85
Type
journal article
Language
en
Open access
Licence
www.elsevier.com/tdm/userlicense/1.0/ (tdm)
Locations
  • Journal of Clinical Epidemiology (publishedVersion)
  • PubMed (publishedVersion)
  • Pure Amsterdam UMC (submittedVersion)
  • Amsterdam UMC (VU Amsterdam) - Institutional Repository (submittedVersion)
  • VU Research Portal (submittedVersion, other-oa)
  • Data Archiving and Networked Services (DANS) (submittedVersion, other-oa)
  • Data Archiving and Networked Services (DANS) (submittedVersion)
Topics
  • Health Sciences › Medicine › Epidemiology › Chronic Disease Management Strategies
  • Social Sciences › Economics, Econometrics and Finance › Economics and Econometrics › Health Systems, Economic Evaluations, Quality of Life
  • Physical Sciences › Mathematics › Statistics and Probability › Statistical Methods in Epidemiology
Keywords
comorbidity measurement, comorbidity index, Charlson Comorbidity Index, Cumulative Illness Rating Scale, validity, reliability statistics, mortality prediction, disability, diabetes mellitus
MeSH terms
Epidemiologic Methods, Health Status Indicators, Humans, Prognosis, Severity of Illness Index, Reproducibility of Results, Comorbidity, Randomized Controlled Trials as Topic

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