Geographic variation in primary care visits in Iowa.
OBJECTIVE
This study investigates the determinants of primary care office visit rates.


METHODS
Blue Cross and Blue Shield of Iowa subscriber information was sorted by residence into geographic health service areas. Cost-sharing information was also obtained from Blue Cross. Physician supply data were obtained from The University of Iowa, Office of Community-Based Programs. Hospital data were reported by the Iowa Hospital Association.


METHODS
Cases were classified into ambulatory care groups (ACGs). Use rates were computed for each group in each service area. Ordinary least squares regression models were developed to model geographic variation in each ACG-specific primary care visit rate.


RESULTS
Regression models were not significant for five out of eleven ACGs studied. Out-of-pocket expense significantly affected utilization in three out of six. The number of primary care practices per capita had a significant effect on utilization in two ACGs. The supply of hospital outpatient services was significant in one ACG.


CONCLUSIONS
Study findings reveal that some ACGs are price-sensitive and some are not. Policies aimed at changing levels of primary care use should taken into account whether varying cost-sharing will influence consumer behavior in the desired direction.
Graduate Program in Hospital and Health Administration, University of Iowa, Iowa City 52242, USA.
L W
LW
Briggs
J E
JE
Rohrer
R L
RL
Ludke
P E
PE
Hilsenrath
K T
KT
Phillips
D000328:Adult; D000553:Ambulatory Care / Q000145:classification / Q000706:statistics & numerical data; D054598:Blue Cross Blue Shield Insurance Plans / Q000706:statistics & numerical data; D002391:Catchment Area, Health / Q000706:statistics & numerical data*; D003953:Diagnosis-Related Groups / Q000706:statistics & numerical data; D005260:Female; D005843:Geography; D005102:Health Expenditures / Q000706:statistics & numerical data; D006297:Health Services Accessibility / Q000706:statistics & numerical data; D006302:Health Services Research; D006801:Humans; D007484:Iowa; D008297:Male; D009819:Office Visits / Q000706:statistics & numerical data*; D010820:Physicians / Q000706:statistics & numerical data / Q000600:supply & distribution; D011320:Primary Health Care / Q000706:statistics & numerical data*; D012044:Regression Analysis; D017062:Small-Area Analysis