Electroconvulsive therapy (ECT) for depression is a controversial treatment with highly polarised views about the balance between therapeutic benefits and adverse effects. Studies investigating whether ECT is more effective than a placebo treatment started in the 1950s, with the most important randomised controlled studies carried out about four decades ago in which ECT was compared with sham ECT involving anaesthesia but no electrically-induced seizure. Subsequently the data have been pooled in a number of meta-analyses which have found that ECT is an effective treatment. However a recent review of the quality of the sham ECT-controlled studies, and the meta-analyses based on them, concludes that their quality is too poor to allow assessment of the efficacy of ECT, and that given its risks (permanent memory loss and death) the use of ECT should be suspended. This commentary critically discusses the methodology of this review and its conclusions.