Intervention with feedback using Outcome Questionnaire 45 (OQ-45) in a Swedish psychiatric outpatient population. A randomized controlled trial

Aim: The objective of the study was to evaluate the efficacy of the Outcome Questionnaire 45 (OQ-45) with feedback in a Swedish psychiatric outpatient population using a randomized controlled design. Method: In all 1720 patients made at least one regular visit to the clinics in the period 12 February 2007 to 10 February 2008 and received information about the study. Of these, 374 patients (22%) agreed to participate. After written consent, 188 patients were randomized to the feedback group and 186 patients to the control group. Those constituted the intention-to-treat (ITT) group. Two hundred and sixty-two patients (70%) completed the OQ-45 questionnaire at least twice, and they were included in the per-protocol analysis. Those who improved less than expected and were at risk for treatment failure were called alerted patients. Results: There was a tendency that patients who received feedback improved more than the controls in OQ-45 total score. In the ITT analysis, the P-value was 0.061 and the effect size g = 0.21. In the per-protocol analysis the P-value was 0.076 and the effect size g = 0.24. In the intervention group, 27% of the patients were alerted because of risk of treatment failure vs. 28% in the control group (reaching level of alertness). The OQ-45 differences between the intervention and control groups did not significantly differ for patients who were alerted/reaching level of alertness and for non-alerted patients (g = 0.17 and g = 0.28, respectively). Conclusions: The feedback group had a tendency to improve more than the control group, possibly indicating that the method is effective, and the result (basically) supports previous findings.