Sensitivity of medication use to formulary controls in medicare beneficiaries: a review of the literature.

Background: Several studies have examined the impact of formulary management strategies on medication use in the elderly, but little has been done to synthesize the findings to determine whether the results show consistent trends.

Objective: To summarize the effects of formulary controls (ie, tiered copays, step edits, prior authorization, and generic substitution) on medication use in the Medicare population to inform future Medicare Part D and other coverage decisions.

Methods: This systematic review included research articles (found via PubMed, Google Scholar, and specific scientific journals) that evaluated the impact of drug coverage or cost-sharing on medication use in elderly (aged ≥65 years) Medicare beneficiaries.