CBT is as effective as continued antidepressant treatment in preventing subsequent relapse, a meta-analysis has found. Nine studies with a total of 506 participants met the inclusion criteria; seven were from the USA, one from the UK and one from Romania. The average Hamilton Depression Rating Scale scores at recruitment ranged from 18.4 to 26.9, indicating moderate to severe depression. Patients were randomised to receive either CBT (18-24 sessions) or antidepressants during the acute phase (12-16 weeks). CBT was not continued during the follow-up period, although a maximum of five booster sessions were allowed. Antidepressant treatment was either continued during the follow-up period, or withdrawn.