Does enhanced meaning after meaning-centered group psychotherapy mediate a reduction in depressive symptoms in cancer survivors? A mediation analysis in the context of a randomized controlled trial

Purpose: After meaning-centered group psychotherapy for cancer survivors (MCGP-CS), depressive symptoms tend to decrease. An enhanced sense of meaning may play a mediating role in this decrease. The aim of this study was to assess whether personal meaning mediates the relationship between MCGP-CS and depressive symptoms. Methods: Cancer survivors (n = 114) were randomly allocated to MCGP-CS or care as usual (CAU). The assessments were scheduled at baseline, postintervention, and at 3- and 6-month follow-up. Mediation models were estimated based on structural equation modeling. We computed the indirect effect of MCGP-CS on depressive symptoms at the 3-month follow-up through personal meaning, and other meaning-related mediators, measured postintervention. Results: A small but significant indirect effect of MCGP-CS on depressive symptoms at the 3-month follow-up was found through personal meaning postintervention (b = − 0.29, 95% bootstrap CI (− 0.63, − 0.03)). There were no significant indirect effects through the other meaning-related factors. Conclusions: This study tentatively supports the MCGP-CS working model in that an enhanced sense of meaning as a result of MCGP-CS mediates a reduction in depressive symptoms. Personal meaning mediated a small effect of MCGP-CS on depressive symptoms. The longitudinal mediating effect of personal meaning occurred within a time period of 3 months after MCGP-CS. Relevance: MCGP-CS is a psychological intervention that supports cancer survivors in regaining or enhancing a sense of meaning in their lives. This enhanced sense of meaning is a protective factor against depressive symptoms. Trial registration: The RCT was registered in the Netherlands Trial Register (number NTR3571/NL3421) on August 10, 2012.