A quasi-experimental design evaluating salient factors of successful and unsuccessful clients in a drug treatment program




Maclean, Bruce Miller.

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Purpose The objective of this study was threefold: (1) to determine if certain personality characteristics, as defined by the MMPI, would distinguish successful drug addiction rehabilitates from those who were not successful; (2) to evaluate unsuccessful program applicants to determine what changes in personality characteristics occurred based on length of time in treatment, and; (3) to determine changes in personality characteristics of successful clients. Methods A quasi-experimental design was utilized. Two unsuccessful and one successful groups were selected and tested with MMPI up to three times over an eighteen month continuum based on time spent in treatment. Mean scores were determined for each of the groups on each of the thirteen scales and analyzed statistically with analysis of variance and the “t” test. Findings There were significant differences between successful and unsuccessful clients on scales F and 8 (Schizophrenia) on the pre-test comparisons with successful clients having lower mean elevations. Scales F and 6 (Paranoia) appeared to distinguish unsuccessful clients who spent at least six months in treatment from those who would be successful program graduates. Unsuccessful clients who spent at least six months in treatment achieved significant reductions on scales 1 (Hypochondriasis), 2 (Depression), and 6 (Paranoia) and a significant increase on scale 5 (Masculine-Feminine). Successful clients had statistically significant changes on 1 of 3 validity scales and 8 of 10 clinical MMPI scales evaluated.



Drug abuse--Treatment, Drug abuse--Forecasting, Drug addicts--Rehabilitation