THE SYMPTOM CHECK LIST 90-R (SCL-90-R) FOR PRESENTING STATISTICALLY AND CLINICALLY SIGNIFICANT RESULTS OF PSYCHOTHERAPY

After a long period of discussions on the efficacy of psychotherapy, t here is still a lack of conventions for measuring change after psychol ogical treatment. This paper first describes the concept of statistica l and clinical significance of change. Using thg SCL-90-R as a commonl y administered instrument we then propose conventions and cut-off poin ts for its global severity score (GSI) and change after therapy. A Ger man standard population and several psychotherapy samples were aggrega ted to determine cut-off points and confidence intervals (reliable cha nge indices) for statistically and clinically significant changes. Tin gey et at. (1996) proposed the use of multiple clinical groups (inpati ents and outpatients) aiming at a more realistic determination of ''st epwise'' changes. We examined this procedure with our data. Results sh ow that it is not applicable in the German samples collected so far. I nitial SCL-90-R scores in these groups did not differentiate sufficien tly between inpatients and outpatients. Therefore, according to jacobs on and Truax (1991), moving from a ''functional'' to a ''dysfunctional '' population is still the criterion for a clinically significant chan ge.