GEOGRAPHIC-VARIATION IN PRIMARY-CARE VISITS IN IOWA

Objective. This study investigates the determinants of primary care of fice visit rates. Data Sources. Blue Cross and Blue Shield of Iowa sub scriber information was sorted by residence into geographic health ser vice areas. Cost-sharing information was also obtained from Blue Cross . Physician supply data were obtained from The University of Iowa, Off ice of Community-Based Programs. Hospital data were reported by the Io wa Hospital Association. Study Design. Cases were classified into ambu latory care groups (ACGs). Use rates were computed for each group in e ach service area. Ordinary least squares regression models were develo ped to model geographic variation in each ACG-specific primary care vi sit rate. Principal Findings. Regression models were not significant f or five out of eleven ACGs studied. Out-of-pocket expense significantl y affected utilization in three out of six. The number of primary care practices per capita had a significant effect on utilization in two A CGs. The supply of hospital outpatient services was significant in one ACG. Conclusions. Study findings reveal that some ACGs are price-sens itive and some are not. Policies aimed at changing levels of primary c are use should take into account whether varying cost-sharing will inf luence consumer behavior,in the desired direction.