Cover: Natural Classes of Treatment Response

Natural Classes of Treatment Response

Published in: Journal of Consulting and Clinical Psychology, v. 65, no. 4, Aug. 1997, p. 673-685

Posted on 1997

by Andrew R. Morral, Martin Y. Iguchi, Mark A. Belding, Richard J. Lamb

This study examines an approach to identifying patterns of treatment response over time. Treatment response profiles are identified by cluster analyzing a repeated measure of patient performance collected at intervals during treatment. The procedure is demonstrated in Study 1 using monthly urinalysis results of 103 patients entering methadone maintenance treatment. The internal, external, and face validities of derived treatment response profiles are evaluated. A logistic regression model predicting treatment response is then constructed from intake variables found to correspond with the treatment response profiles. Study 2 replicates the procedures on an independent sample. Treatment response profiles facilitate the analysis of treatment response offering advantages over common measures of treatment outcome, such as performance at follow-up, change in performance from treatment entry to follow-up, or performance summed across treatment.

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