Sources Accounting for Alliance and Cohesion at Three Stages in Group Psychotherapy: Variance Component Analyses

This study examined patient, therapist, and group variability accounting for alliance and cohesion over three stages in a sample of 145 patients attending short- and long-term psychodynamic group therapy. G-study variance components were estimated for the 14 sources of variation identifiable by the research design. Results indicated that patient variability represented the strongest clinically relevant contribution to both alliance and cohesion. Therapists were important for alliance at all stages, but for cohesion only in the middle stage. The therapist X group interaction was important to the alliance in early therapy and for cohesion within the two first stages, but this contribution then decreased. Group length did not account for any variability in the process measures. Theoretical implications were discussed.