Related Experiment Video
Updated: Jun 1, 2026
Inverse Probability of Treatment Weighting (Propensity Score) using the Military Health System Data Repository and National Death Index
Published on: January 8, 2020
Identifying chronic conditions in Medicare claims data: evaluating the Chronic Condition Data Warehouse algorithm
Yelena Gorina1, Ellen A Kramarow
1Centers for Disease Control and Prevention, National Center for Health Statistics, Office of Analysis and Epidemiology, 3311 Toledo Road, Room 6332, Hyattsville, MD 20782, USA.
Objective:
To examine the strengths and limitations of the Center for Medicare and Medicaid Services' Chronic Condition Data Warehouse (CCW) algorithm for identifying chronic conditions in older persons from Medicare beneficiary data.
Data Sources:
Records from participants of the NHANES I Epidemiologic Follow-up Study (NHEFS 1971-1992) linked to Medicare claims data from 1991 to 2000.
Study Design:
We estimated the percent of preexisting cases of chronic conditions correctly identified by the CCW algorithm during its reference period and the number of years of claims data necessary to find a preexisting condition.
Principal Findings:
The CCW algorithm identified 69 percent of preexisting diabetes cases but only 17 percent of preexisting arthritis cases. Cases identified by the CCW are a mix of preexisting and newly diagnosed conditions.
Conclusions:
The prevalence of conditions needing less frequent health care utilization (e.g., arthritis) may be underestimated by the CCW algorithm. The CCW reference periods may not be sufficient for all analytic purposes.
Related Concept Videos
01:15Methods of Documentation VI: Case Management Model
For example, a patient with a chronic illness...
01:29Documentation in Long-Term and Home Healthcare Setting
Long-Term Care Facilities
01:30Health Information Technology and Healthcare Information System
Health Information Technology, commonly called HIT, integrates advanced information systems and technology in healthcare settings. Its primary functions include:
01:10Documentation of Nursing Diagnosis
In some settings, data-driven computerized decision support systems are in place, allowing for more accurate nursing diagnoses. The database within one of these systems includes diagnostic labels defining characteristics, activities, and indicators for nursing. A nurse enters assessment...
01:23Methods of Documentation V: CBE
In CBE, healthcare professionals establish predefined standards of practice that define what constitutes...
01:27Chronic Obstructive Pulmonary Disease-IV: Assessement and Diagnostic Studies
Medical History