Published RCTs in EOS differed substantially in sample size and methodology, and this made comparison and generalization somewhat difficult. Initial studies included at most 50 patients,7–9,11 ie, subject numbers that would have been barely acceptable in adult psychiatry due to an underpowered design. The situation only improved in 2008 when the first larger and better designed studies appeared; a remarkable and noteworthy delay compared with adult psychiatry. Most studies lasted 6 weeks, but some lasted 8 weeks, and one study in treatment-resistant patients lasted 12 weeks (Table 1).