Does One Size Fit All? Moderators in psychosocial interventions for breast cancer patients: A meta-analysis

Background: A variety of psychosocial interventions have been developed to promote better adjustment to breast cancer (BC) and their efficacy has been demonstrated repeatedly. However, the effect sizes (ES) vary considerably across studies. Purpose: This article intends to shed light on potential moderators of intervention efficacy for BC patients, such as the intervention type (e.g., education, supportive), the composition of the sample (only BC patients or BC mixed with other cancer types), and the practitioner of the intervention (psychologist, nonpsychologist). Methods: Fifty-six randomized-controlled studies investigating the effectiveness of psychosocial interventions with adult BC patients were meta-analytically reviewed Results: The overall ES of d = 0.26 was similar to previous meta-analyses and moderated by several variables. The ES varied notably based on the composition of the sample, the profession offering the intervention, and the type of intervention. Studies with samples consisting of only BC patients and studies with nonpsychologist-led interventions showed lower ES. Psychoeducation yielded the strongest ES. These moderators maintained their significance even when controlling for the nature of the control group, the format of the intervention, the timing of the intervention, or the stage of disease. Conclusions: These results suggest that among current interventions, psychoeducation is a treatment of choice for BC patients, preferably prior to surgery and led by individuals with a medical expertise. Other psychosocial interventions appear most effective when administered individually and led by a psychologist. In addition, there is a need for improved psychosocial interventions to enhance the present ES for women with BC.