Dec 31, 2000
The authors analyzed data from the RAND Health Insurance Experiment, a randomized controlled trial of the effect of cost sharing on the use of health services. Families in six U.S. sites were randomized to receive fee-for-service care that was free or required one of several levels of cost sharing, or to receive care from a health maintenance organization (HMO). Enrollees were followed for 3 or 5 years. All fee-for-service plans covered chiropractic services. Persons assigned to the HMO experimental group received free fee-for-service chiropractic care; persons on the HMO control group had 95% cost sharing for chiropractic services. The authors calculated the mean annual chiropractic expense per person in each of the fee-for-service plans, and also predicted their chiropractic expenditures using a two-equation model. Chiropractic use among persons receiving HMO and fee-for-service care were compared. The authors conclude that chiropractic care is more sensitive to price than general medical care, outpatient medical care, or dental care, and nearly as sensitive as outpatient mental health care. A substantial cross-price effect with medical care may exist.