Despite a general consensus that cohesiveness promotes positive outcomes in group psychotherapy, the empirical evidence for this notion is limited. In this article the literature on group cohesiveness and its relation to clinical outcomes is reviewed. Three interrelated problems with this literature are highlighted: A lack of consensus as to how to conceptualize cohesiveness, inconsistent measurements of cohesiveness, and lack of attention to possible mediators of the cohesiveness-outcome relationship. The authors argue that the term cohesiveness is too vague and amorphous to be useful as a unitary construct and that the field could benefit by identifying more specific group processes that facilitate—or impede—clinical outcomes. They review social psychological research on group processes, and discuss how three constructs— group identification, independence, and homogeneity—might be applied to the clinical literature. Furthermore, in an attempt to stimulate a closer examination of mediational paths in the literature on group psychotherapy, they discuss possible mechanisms through which group processes affect clinical outcomes.

two studies (N = 109 anxious and depressed patients; N = 94 depressed patients) investigated the role of autonomy as described in self-determination theory as a mechanism of therapeutic change in cognitive behavioral group therapy. Across both studies, results showed that higher need satisfaction for autonomy is related to improved outcomes, and that this relationship is mediated by improvement in cognitions. these findings support the tenets of self-determination theory in that patients who perceived their autonomy needs are satisfied while participating in cognitive behavioral group therapy experienced a greater reduction in negative thinking which was in turn related to more positive therapy outcomes.

Although it is widely assumed that cohesiveness promotes positive outcomes in group psychotherapy, the empirical evidence for this notion is very limited. In light of persistent confusion over how it should be conceptualized and measured, we argue that the term "cohesiveness" is too amorphous to serve as an adequate organizing principle for theory and research, and that it should be replaced with more cogent and specific alternatives. Drawing on social psychological literature, we also question the intuitive notion that cohesiveness necessarily leads to positive outcomes. To the extent that the need for harmony is prioritized over the need for personal expression, dissent, and challenge, then it could be that cohesiveness might have negative as well as positive implications for members of group therapy.

Recent literature has shown that group cognitive-behavioral therapy (CBT) is effective for individuals with heterogeneous anxiety disorders. However, these studies have used a narrow range of outcome measures, and have not included global measures such as quality of life. In addition, heterogeneous mood disorders have not been well researched. The aim of this study was to replicate and extend on previous studies by assessing the effectiveness of group CBT treatment programs designed for use with heterogeneous anxiety or depressive disorders. Global outcome measures of quality of life and social functioning were assessed in addition to outcome measures of anxiety and mood symptoms. There were 173 patients who completed either group CBT for anxiety disorders or for depressive disorders. Symptom measures and quality of life measures were used to determine treatment effectiveness. Results demonstrated that the treatments were effective in reducing overall symptom severity and improving quality of life. Treatment gains were maintained to 12 month follow-up. However, the degree of change was considerably lower than that found in comparable trials with diagnostically homogenous samples. Overall, group CBT for heterogeneous diagnostic populations was effective but requires further investigation and refinement.