Illness severity and total visits in family medicine

The purpose of this study was to estimate the independent effect of clinical severity on visit utilization by family medicine patients so that disease management programmes can be targeted accurately and immediately towards patients most likely to benefit from them.

A convenience sample of 698 primary care patients was analysed. All patients had been referred to a medical specialist. Utilization of all types of medical services including laboratory, radiology and ancillary services was used to classify patients as high-utilizers (the top 20%) or not high-utilizers. Patients were stratified into three severity categories based on point scores assigned to specific diseases. The diagnoses included in the Charlson severity index were used to score each patient and the Charlson point scores were used to measure severity. The odds of being a high-utilizer were adjusted for severity category and demographic variables.

Severity was independently related to the odds of being a high-user (adjusted odds ratio = 2.7 for severity = 1 and 5.7 for severity = 2, with the reference category being severity = 0). Age was related to high-use in univariate analyses but not in multivariate analyses.

Case management programmes in primary care practices should consider using disease severity to identify cases. Severity data can be abstracted by medical secretaries who review narrative problem lists as well as billing codes.