“…5) The presence of inter-study variability between sham and not sham studies was not ascribable to mean or median age of patients but possibly to other factors. 6) The absence of psychological and psychiatric profile that is relevant for studies were the placebo effect have to be evaluated represents a very important confounding factor [10], [22], [24], [25], [26], [27], [28], [29], [30], [31], [32], [33], [34], [35], [36], [37], [38], [39], [40], [41], [42], [43], [44], [45], [46], [47], [48], [49], [50], [51], [52], [53], [54], [55], [56], [57], [58], [59], [60], [61], [62], [63], [64], [65], [66], [67], [68], [69], [70], [71], [72], [73], [78], [79]. 7) A percentage of 5% of participants lost to the follow-up has been extracted from 30 on the 52 studies examined (ref.).…”