<p>Background The concept of self-efficacy has been proposed as a suitable outcome measure in psychiatry. Self-efficacy refers to an individual’s belief that he or she can control important aspects of his or her life. An audit of 67 consecutive clients attending an acute psychiatric day unit was conducted, measuring self-efficacy at admission to the unit and at discharge.</p> <p>Conclusion The concept of self-efficacy was easily explained to clients, and was measured using a 15-point questionnaire. Self-efficacy increased following treatment in the day unit, and this increase appears to reflect an underlying change in the individual’s self-belief.</p>