How Sick Is My Cohort of Patients? A General Approach to Identify Chronic Conditions

Analysis of medical claims data frequently requires identifying a disease cohort or controlling for chronic conditions. The Chronic Conditions Warehouse ( applies validated algorithms for discerning multiple chronic conditions in Medicare claims data, and CMS provides the results of their application with Medicare claims data if requested. The algorithms use a combination of diagnosis and procedure codes and selection rules, which vary among conditions. For example, to eliminate rule-out diagnoses, the algorithm for diabetes requires one set of diagnosis codes observed on any inpatient or skilled nursing facility claim, or two claims at least a day apart on a physician claim. This presentation discusses a SAS(r) macro that applies CCW-like rules to any data set either from insurance claims, or electronic health records (EHR) containing a full picture of diagnoses and procedures from patient medical visits. The macro package includes the CCW-validated algorithms (the default option), but also has the flexibility for the user to apply the algorithm to a different set of diagnoses and procedures. The user can either implement variations of the CCW definitions or identify entirely new conditions, so long as they can be implemented using diagnosis or procedure codes, claim types and CCW-like rules. The macro package is described, including how its applied to medical claims from a private insurer.

The full paper is available here.