Fig. 2
Quality appraisal for intervention studies. RCT = randomized controlled trial, LR = low risk of bias, HR = high risk of bias, UR = unclear (insufficient information to permit judgement of low risk or high risk), ITT = intention-to-treat analysis, COPE = Combination Therapy of Hypertension to Prevent Cardiovascular Events, MRC = Medical Research Council. 1 Risk of bias assessed on study protocol [56]