Date of Award
Doctor of Psychology (PsyD)
Graduate Department of Clinical Psychology
Outcome assessment has been used to evaluate the length of treatment needed and has been disputed for some time. Changes within both mental health and health insurance companies have contributed to a trend toward time-limited therapy and the optimal number of sessions has become a central issue. This study sought to extend research in the area of treatment outcome. Specifically. it examined the efficacy of psychotherapy after five and ten sessions on the subjective well-being of university students. Three hypotheses were tested in th.is study: (1) Subjective Well-Being scores (as measured by the Outcome Questionnaire-45. l l) for the treatment group will be significantly higher than those of the control group on the mid and post-tests. (2) Subjective Well-Being scores will be higher for the treatment group subjects tested after five, and ten sessions of individual psychotherapy than the scores of the same subjects on the pretest. (3) Subjective Well-Being scores will be higher for the treatment group subjects tested after ten sessions than the scores of the same subjects after five sessions. The results did not support the three hypotheses as clinically significant change was not demonstrated. When time was compared to group and gender, there were interaction effects. There was a quadratic effect on the interpersonal Relationships scale and a quadratic effect was found when time. group and sex were compared on the Social Role Performance scale. Chi-square analyses were performed and the interpersonal Relationships scale, F(l,19)=3.446; p=.079, approached significance. Although there were no significant group effects found when the two treatment groups were compared, there were three quadratic effects and interaction effects. Future dose-effect studies may benefit from taking their treatment group from a clinical s<1mple. Using a more diverse sample would also be a better representative of the greater population. ln addition, it is proposed that dose-effect studies examine the effects of more or less therapy for a particular problem and avoid seeking to show a particular treatment duration as optimal.
Whitehall, Brian J., "Dose-Effect Relations in Simulated Psychotherapy as Measured by the Outcome Questionnaire-45.11" (2001). Doctor of Psychology (PsyD). 359.