Fig. 1From: Cluster randomised trials with a binary outcome and a small number of clusters: comparison of individual and cluster level analysis methodPerformance measures of cluster-level analysis methods by number of clusters (rows), cluster size and outcome prevalence (colour). Measures shown (columns): Standardised intervention effect estimate bias, standard error bias, type-one error. Each dot represents a scenario summarised over the 1000 repetitions. All 864 scenarios are shown for each measureBack to article page