Table of Contents:
Since the beginning of modern psychology, motivational factors are considered to be important to process and outcome of psychotherapy by practitioners. Research on psychotherapy motivation and therapy outcome shows evidence supporting the importance of this construct. Despite this fact, there is still a lack of a widely acknowledged definition and theoretical conception of psychotherapy motivation. Sufficiently evaluated measurements of psychotherapy motivation are still missing. The scientific tradition of common motivational concepts has rarely been acknowledged by research on psychotherapy motivation. If psychotherapy is considered as a setting where the therapist is helping his patient to reach a certain goal, such as the absence of severe symptoms and the enhancement of social functioning, the concept of achievement motivation might be of relevance. In contrast to psychotherapy motivation, concepts for achievement motivation are thoroughly developed and a variety of valid measures are available. The present study is a first step of integrating the concepts of psychotherapy motivation and achievement motivation in the setting of psychotherapy. The main research question is whether achievement motivation predicts psychotherapy outcome and shows incremental validity above and beyond psychotherapy motivation to predict therapy outcome. Since achievement motivation measurements are more broadly evaluated than psychotherapy motivation measurements the present study is also focusing on the quality of the applied psychotherapy motivation questionnaire. Since the predictive power of psychotherapy motivation on psychotherapy outcome is accepted to be a fact, the research question is concentrating on the construct validity of the psychotherapy motivation questionnaire.
Results show no predictive power of achievement motivation. Findings on the construct validity of the psychotherapy motivation questionnaire are mixed. Particularly the subscale psychological strain, traditionally claimed to be one of the main aspects of psychotherapy motivation, is lacking sufficient relevance with regards to content. Despite this weakness, predictive power for psychotherapyoutcome is given. The motivational concepts are overlapping and the integration of aspects of achievement motivation in the concept of psychotherapy motivation is recommended. Further studies should revise two of the five subscales of the psychotherapy motivation questionnaire. Moreover, to examine the influence of achievement motivation on psychotherapy more precisely, further research should apply motivational measurements at different times during the course of psychotherapy and measure and evaluate psychotherapy outcome on basis of a multi-trait multi-method analysis.