Abstract
Two forms of multiple regression analysis, one based upon a set of individual variables, one based upon a set of orthogonal factors generated from them, were used to predict response to treatment in a group of 199 primarily anxious, neurotic outpatients treated for a 4 week period with either diazepam or phenobarbital. Greater improvement, irrespective of medication received, was found in patients who: 1. enjoyed greater social and personal advantage, 2. participated in a more empathetic treatment relationship, 3. were oriented toward drugs and away from psychotherapy as a primary treatment modality, 4. had less severe presenting symptomatology, and 5. had sufficient cognitive differentiation to realize that their problems were emotional in origin. Diazepam was superior to phenobarbital in employed patients and in patients with more severe somatizing tendencies, while the relative effectiveness of the 2 medications was reversed in unemployed patients and those with limited somatizing tendencies. Weaknesses in one form of regression analysis were complemented by strengths in the other.
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Mr. Dreesmann is a graduate student in psychology, University of Braunschweig, Germany.
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Downing, R.W., Rickels, K. & Dreesmann, H. Orthogonal factors vs. interdependent variables as predictors of drug treatment response in anxious outpatients. Psychopharmacologia 32, 93–111 (1973). https://doi.org/10.1007/BF00428681
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DOI: https://doi.org/10.1007/BF00428681