Figure 1
From: Effectiveness of antidepressants: an evidence myth constructed from a thousand randomized trials?
Anticipated mean and range of average effect size (ES) for trials in countries where a drug is approved, when the true average effectiveness is ES = 0.20 and the standard deviation (SD) of the estimated ES across trials is 0.20, 0.40, and 0.60. Trials are assumed to be of similar size and similar weight in the calculations. Forty approval packages with 5 trials each have been simulated in each of the three settings and the data show the ES in the successful packages (those where the average ES is at least 0.20).