What proportion of primary psychiatric interventions are based on evidence from randomised controlled trials?

OBJECTIVES To estimate the proportion of psychiatric inpatients receiving primary interventions based on randomised controlled trials or systematic reviews of randomised controlled trials. DESIGN Retrospective survey. SETTING Acute adult general psychiatric ward. SUBJECTS All patients admitted to the ward during a 28 day period. MAIN OUTCOME MEASURES Primary interventions were classified according to whether or not they were supported by evidence from randomised controlled trials or systematic reviews. RESULTS The primary interventions received by 26/40 (65%; 95% confidence interval (95% CI) 51% to 79%) of patients admitted during the period were based on randomised trials or systematic reviews. CONCLUSIONS When patients were used as the denominator, most primary interventions given in acute general psychiatry were based on experimental evidence. The evidence was difficult to locate; there is an urgent need for systematic reviews of randomised controlled trials in this area.