Measuring psychological outcomes after cognitive behaviour therapy in primary care: a comparison between a new patient-generated measure “PSYCHLOPS” (Psychological Outcome Profiles) and “HADS” (Hospital Anxiety and Depression Scale)

Abstract

Background: Patient-centred outcome measures are rarely used in primary care mental health settings.

Aim: To determine reliability and change sensitivity for a new patient-generated measure, “PSYCHLOPS” (Psychological Outcome Profiles), comparing those parameters with a conventional outcome measure.

Setting: Patients attending clinical psychology services in primary care.

Methods: Standardized responses to PSYCHLOPS, pre- and post-therapy, were compared with responses to HADS.

Results: 336 patients were recruited; 140 (42%) completed therapy and submitted post-therapy questionnaires. Complete questionnaire data were available for 114 patients (34%). Cohen's Effect Size was 1.61 for PSYCHLOPS and 1.15 for HADS (t = 5.75, p < 0.001). Internal consistency of questionnaire components were 0.75 and 0.67 pre-therapy, respectively. Change scores of both instruments correlated moderately (Pearson's r 0.65; p < 0.001). Completion rates for PSYCHLOPS pre-therapy were: 98.8 %, (problem domain), 91.2%, (function domain), 94.9%, (wellbeing domain) and for HADS, 97.6%.

Conclusion: PSYCHLOPS was a more sensitive measure of change after therapy than the comparator measure, HADS. Strong responsiveness to change, satisfactory internal reliability and high completion rates implying feasibility, all suggest that measuring outcomes based on self-reported changes in problems chosen by patients may be a valuable complement to nomothetic outcome measures and be achieved using PSYCHLOPS.

Keywords:

• Patient-generated outcome measures
• psychometrics
• validation study