ABSTRACT
Normative comparisons are a procedure for evaluating the clinical significance of therapeutic interventions. Although a step-by-step statistical methodology for conducting normative comparisons has been reported elsewhere (P. C. Kendall, A. Marrs-Garcia, S. R. Nath, & R. C. Sheldrick, 1999), questions regarding the collecting of normative data remain. For this study, all treatment outcome studies published in the Journal of Consulting and Clinical Psychology from 1988 to 1997 were examined and reviewed, and the 5 most commonly used outcome measures were identified. For these outcome measures, multiple sources of normative data were located. Although we identified a dearth of normative data on measures used for treatment outcome, results discussed here nevertheless provide information that may be of use to therapy outcome evaluators when conducting normative comparisons. In addition, equations to determine the minimum sample size needed in a normative sample for a given treatment outcome study are provided.
Subject(s)
Mental Disorders/therapy , Psychiatric Status Rating Scales/standards , Reference Standards , Confounding Factors, Epidemiologic , Controlled Clinical Trials as Topic/standards , Data Interpretation, Statistical , Humans , Reference Values , Reproducibility of Results , Research Design/standards , Treatment OutcomeABSTRACT
Normative comparisons are a procedure for evaluating the clinical significance of therapeutic interventions. This procedure, consisting of comparing data on treated individuals with that of normative individuals, is described, and a step-by-step statistical methodology for conducting normative comparisons in the context of treatment-outcome research is presented. Four examples of the methodology are outlined in detail. Attention is paid to potential theoretical, statistical, and methodological challenges to the implementation of normative comparisons, as well as to the advantages of normative comparisons in providing evidence for the beneficial gains of treatment.
