AARP Public Policy Institute’s Rx Price Watch Report: Detailed Methodology and Description of Retail Price Data

This article describes how brand name, generic, and specialty drugs are defined in AARP's Rx Price Watch reports; how the study identified the market basket (i.e., sample) of drugs; how it measures prices; and how it calculates weighted average price changes.It also describes methods and assumptions used to determine prices and price changes by drug manufacturer and by therapeutic category.