The Effect of Plan Characteristics on the Cost of Pharmaceuticals in a Private Third-Party Prescription Program

This study used prescription claims data to evaluate whether average cost of pharmaceuticals differed among various plan characteristics after controlling for covariates and to examine the relationships among plan characteristics and cost of pharmaceuticals within various therapeutic categories. Data for the study were obtained from 1996 prescription claims information for a commercial population administered by a Rhode Island-based PBM. Six therapeutic categories were analyzed. Significant associations were found among plan characteristics and cost of pharmaceuticals. Average cost of pharmaceuticals differed among various plan characteristics such as copayment, mode of payment, formulary status, and pharmacy type after controlling for average wholesale price and days\u27 supply. © 2000, Informa UK Ltd All rights reserved: reproduction in whole or part not permitted. All rights reserved