The stepped wedge design to evaluate the effect of the CME. The first time point to the left indicates the baseline measurement where all of the clusters were controls (C). At subsequent time points, clusters received the CME intervention and crossed over to interventions (I). All clusters eventually received the intervention. The bottom of the figure focuses on one cluster to illustrate the data collection and the three subgroups for stratification: 1) GPs who participated in the CME; 2) GPs who did not participate in the CME, but who had at least one colleague who participated; 3) GPs who did not participate in the CME and who had no colleagues who participated.