Estimating the price elasticity of demand through value-based formulary designs

In 2010, Premera Blue Cross (Premera), a large nonprofit health plan in the Pacific Northwest implemented a value-based formulary design for its beneficiaries.   In essence, enrollees could purchase high-value treatments for low copayments and low-value treatments for higher copayments.  Can we use this change from more standard to value-base formulary designs to estimate the price elasticity…