What is an adequate therapy model? Implications for clinical psychology

The purpose of this study is to define what constitutes a robust therapy theory by proposing specific criteria and applying them to three psychotherapy models. This aims to provide clinicians with a structured framework for understanding and explaining patient experiences, organising relevant information, and implementing effective treatments. The criteria chosen for this theoretical article were based on discussions between the first and second authors, as well as on previous publications. The proposed criteria, named GROW-P, require models to be generic, applicable across various contexts, and to elucidate mechanisms of change distinct from outcomes. These processes should be observable and specified at a within-person level. The analysis shows that meeting these criteria enhances the clarity and interpretability of comparative treatment studies. Well-defined mechanisms of change contribute to a systematic understanding of psychotherapy processes, support the formulation of testable hypotheses, and improve treatment outcomes. This approach advances both scientific knowledge and clinical practice in mental health.