Clinically significant change in psychotherapy for depressive disorders

Abstract

Background: The assessment of change has been a problematic issue in psychotherapy research and has become increasingly important in the up rise of evidence-based practices.

Methods: In the present paper, the clinical significance of the change of 243 patients who received one of nine treatments for depression was analysed using the Reliable Change Index [Jacobson, N.S., Follette, W.C., Revenstorf, D., 1984. Psychotherapy outcome research: Methods for reporting variability and evaluating clinical significance. Behav. Ther. 15, 336-352.] and normative comparisons (Equivalency Testing; [Kendall, P.C., Marrs-Garcia, A., Nath, S.R., Sheldrick, R.C., 1999. Normative comparisons for the evaluation of clinical significance. J. Consult. Clin. Psychol. 67, 285-299.]). While the first method addresses the question of whether or not the change that occurred was large enough to be attributable to treatment rather than to measurement error, the second method addresses the issue of comparing the level of functioning of treated individuals with non-clinical population. Hence, the nine treatments of depression were compared in terms of their reliability and clinical significance. Traditional statistical tests in treatment outcome studies were also conducted.

Results: Findings support the importance of analysing the clinical significance of change during psychotherapy. While all but one treatment led to statistical significant changes in depressive symptoms, differences among treatments were found in terms of their reliability and clinical significance.

Limitations: Small sample sizes and representativeness of each treatment warrant further replication of these results.

Conclusions: Implications of the use of clinical significance testing in the exploration of empirical support for psychotherapy treatments in conjunction with traditional statistical analyses are discussed, which will be more readily useful and meaningful to clinicians who wish to embark in evidence-based practices.