Funding for this study was provided internally by Express Scripts Holding Company. The authors and acknowledged contributors are employees of Express Scripts Holding Company. All authors contributed to the study concept, and study design was provided by Munshi, Mager, and Henderson. Munshi and Mager collected the data, and Munshi provided the statistical analysis. Data interpretation was performed by Munshi, Mager, and Henderson. The manuscript was written by Munshi, Henderson, and Mager and revised by Munshi, Ward, Mischel, and Henderson.