Utilization of child health clinics following introduction of a copayment.

The effect of introduction of a copayment on utilization of well child services was investigated in St. Mary's County, Maryland between 1975 and 1979. Utilization declined between the pre-copayment and post-copayment periods for White and non-White infants under six months of age. The deterrent impact of the copayment suggested by the results may be related to crossover to private care but may also represent a drop in use of preventive services.