Fig. 1From: Sample size calculation for a stepped wedge trialPower curves for a continuous outcome assuming: 25 clusters, each with 20 subjects; 6 time points including one baseline. We varied the intervention effect size and the ICC variations. Panel (a) shows the analysis for a repeated closed cohort (cross-sectional) design, while panel (b) depicts the results for a closed cohort design. In panel (b) the selected ICCs are reported for cluster and participant levelBack to article page