title: Defining early positive response to psychotherapy: An empirical comparison between clinically significant change criteria and growth mixture modeling.
abstract: Several different approaches have been applied to identify early positive change in response to psychotherapy so as to predict later treatment outcome and length as well as use this information for outcome monitoring and treatment planning. In this study, simple methods based on clinically significant change criteria and computationally demanding growth mixture modeling (GMM) are compared with regard to their overlap and uniqueness as well as their characteristics in terms of initial impairment, therapy outcome, and treatment length. The GMM approach identified a highly specific subgroup of early improving patients. These patients were characterized by higher average intake impairments and higher pre- to-posttreatment score differences. Although being more specific for the prediction of treatment success, GMM was much less sensitive than clinically significant and reliable change criteria. There were no differences between the groups with regard to treatment length. Because each of the approaches had specific advantages, results suggest a combination of both methods for practical use in routine outcome monitoring and treatment planning.
authors.affiliation: Department of Clinical Psychology and Psychotherapy.
authors.forename: Julian
authors.initials: J
authors.lastname: Rubel
authors.affiliation: Department of Clinical Psychology and Psychotherapy.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Lutz
authors.affiliation: Department of Psychology, University of Evansville.
authors.forename: Stephen Mark
authors.initials: SM
authors.lastname: Kopta
authors.affiliation: Outpatient Clinic for Psychotherapy, University of Koblenz-Landau.
authors.forename: Katharina
authors.initials: K
authors.lastname: Köck
authors.affiliation: College of Education and Human Development, University of Massachusetts Boston.
authors.forename: Takuya
authors.initials: T
authors.lastname: Minami
authors.affiliation: Department of Clinical Psychology and Psychotherapy.
authors.forename: Dirk
authors.initials: D
authors.lastname: Zimmermann
authors.affiliation: Stephen M. Saunders, Department of Psychology, Marquette University.
authors.forename: Stephen M
authors.initials: SM
authors.lastname: Saunders
mesh_terms: D000293:Adolescent; D001007:Anxiety / Q000628:therapy*; D001499:Bayes Theorem; D003863:Depression / Q000628:therapy*; D005260:Female; D006801:Humans; D016014:Linear Models; D008297:Male; D015233:Models, Statistical; D011613:Psychotherapy; D013333:Student Health Services; D016896:Treatment Outcome; D055815:Young Adult