Figure 1From: Design, rationale, and baseline characteristics of a cluster randomized controlled trial of pay for performance for hypertension treatment: study protocol Randomization schematic. ALLHAT = Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial; VA = Veterans Administration. *Enrolled up to seven primary care physicians at each study site. †Enrolled up to 15 non-physician participants (e.g., nurses and pharmacists) at each study site.Back to article page