Measuring Underuse of Necessary Care Among Elderly Medicare Beneficiaries Using Inpatient and Outpatient Claims

CONTEXT Continuing changes in the health care delivery system make it essential to monitor underuse of needed care, even for relatively well-insured populations. Traditional approaches to measuring underuse have relied on patient surveys and chart reviews, which are expensive, or simple single-condition claims-based indicators, which are not clinically convincing. OBJECTIVE To develop a comprehensive, low-cost system for measuring underuse of necessary care among elderly patients using inpatient and outpatient Medicare claims. DESIGN A 7-member, multispecialty expert physician panel was assembled and used a modified Delphi method to develop clinically detailed underuse indicators likely to be associated with avoidable poor outcomes for 15 common acute and chronic medical and surgical conditions. An automated system was developed to calculate the indicators using administrative data. SETTING AND SUBJECTS A total of 345,253 randomly selected elderly US Medicare beneficiaries in 1994-1996. MAIN OUTCOME MEASURES Proportion of beneficiaries receiving care, stratified by indicators of necessary care (n = 40, including 3 for preventive care), and avoidable outcomes (n = 6). RESULTS For 16 of 40 necessary care indicators (including preventive care indicators), beneficiaries received the indicated care less than two thirds of the time. Of all indicators, African Americans scored significantly worse than whites on 16 and better on 2; residents of poverty areas scored significantly lower than nonresidents on 17 and higher on 1; residents of federally defined Health Professional Shortage Areas scored significantly lower than nonresidents on 16 and higher on none (P