Clinically Sensitive Cost-Sharing for Prescription Drugs. Thinking Beyond the Silos

Researchers, actuaries, and health care purchasers have known for decades that, as a general principle, higher patient cost sharing reduces utilization of health care services and consequently, health care spending. Evidence on this point includes the seminal RAND Health Insurance Experiment, which used a randomized controlled study design1, as well as numerous recent studies,2–7 for a review, see Rice & Morrison (1994). This conventional wisdom applies to health care in aggregate, but increasingly purchasers are interested in specific services. Because of the rapid increase of spending on prescription drugs, cost sharing for pharmaceuticals has attracted considerable attention. (May 2009)