Relatedness as an indicator of group cohesion and its relationship to outcomes of a group-based CBSM intervention for women who have completed treatment for breast cancer

Group delivered empirically supported therapies have been reported to have beneficial effects for cancer patients. However, little is known about the relationship between group cohesion and outcomes of these interventions. This study tested the hypothesis that group cohesion relates to the effects of a group intervention. Participants included 56 women with Stage I-II breast cancer who had completed a 10-week CBSM intervention 3--12 months after undergoing surgery and adjuvant therapy. Groups of 3--5 participants met weekly for sessions of approximately 1 hour and 45 minutes duration. All participants were assessed at baseline (2 weeks prior to beginning the intervention) and at follow-up (12 weeks after enrollment in the study). Cohesion was measured at the end of each intervention session by External Comfort (EC), a factor of the relatedness scale of the Stuttgarter Bogen instrument (1976). EC denotes an aspect of the individual's sense of comfort within the group that is dependent on how the group participant relates to other members. EC score for session 9 (EC9), and change in EC from session 2 to session 9 (calculated as a change score, i.e., session 9 score minus session 2 score), were used for analyses as independent variables in simple linear regression models. Dependent variables were also calculated as a change score (i.e., follow-up minus baseline) and included benefit finding (Post Traumatic Growth Inventory PTGI, total score and its 5 factors), depression (CESD), urinary cortisol, and natural killer cell function (total percent, number and cytotoxicity). Results yielded a positive change in EC from session 2 to session 9 (M=2.29, S.D.=2.67). Regression analyses indicated a significant negative relationship between change in EC9 and change in total PTGI scores (beta=-.450, p=.011), and change in Factor 1 Relating to Others (beta=-.414, p=.021). A marginally significant negative relationship was observed between change in EC from session 2 to session 9 and the New Possibilities Factor of the PTGI (beta=-.323, p=.077). A median split, by change in EC, indicated that participants with high EC scores throughout the intervention showed an increase in total PTGI scores, and in two of the five PTGI factors at follow-up. In contrast, participants who initially scored lower values in EC showed no change in these variables. These results suggest that the longer it takes an individual to feel comfortable in the group, the less the individual would be able to find benefit from their cancer experience after the intervention.