Background: The Mental Health subscales of the Medical Outcomes Short Form Questionnaire (SF-36; [Ware, J.E., Snow, K.K., Kosinski, M., Gandek, B., 1993. SF-36 Health Survey: Manual and Interpretation Guide. Boston: The Health Institute, New England Medical Center]) are increasingly being used to evaluate treatment outcomes, but data to assess the clinical significance of changes are absent. The present study applied Jacobson and Truax's [Jacobson, N.S., Truax, P. 1991.
Clinical significance: a statistical approach to defining meaningful change in psychotherapy research. Journal of Consulting and Clinical Psychology 59, 12-19] criteria for clinical significance to the mental health items of the SF-36.
Method: Admission and discharge data were collated from 1830 consecutive inpatients at a psychiatric hospital, using the SF-36, the Depression Anxiety Stress Scale, the Quality of Life Enjoyment and Satisfaction Questionnaire and the clinician-rated Health of the Nation Outcome Scale.
Results: Appropriate improvement cut-off scores for the mental health subscales of the SF-36 are reported, and significant differences were found between outcome groups according to clinically significant improvement.
Limitations: CLINICAL SIGNIFICANCE as a means of assessing outcome should be used with caution in inpatient settings, as further improvement is often expected upon discharge from the hospital.
Conclusions: Assessing clinically significant improvement is an effective means of measuring treatment outcome in terms of quality of life and symptom improvement in psychiatric care.