Psychological and spiritual interventions to enhance meaning in adults diagnosed with cancer: a systematic review with meta-analysis and meta-regression

Objective To summarize the evidence on the effectiveness that psychological and/or spiritual interventions may have to change the levels of meaning, measured with the Functional Assessment of Chronic Illness Therapy-Spiritual Well-Being Scale (FACIT-Sp), in adults diagnosed with cancer.Methods Systematic review with meta-analysis and meta-regression. CINAHL (via EBSCOhost), Embase, PubMed, PsycINFO (via ProQuest), and the Cochrane Library were searched from inception to 21(st) October 2022. Manual searches were conducted. Only randomized clinical trials (RCTs) were included. The risk of bias was assessed with the Cochrane Risk of Bias tool 2. The Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) approach was used to judge the certainty of the evidence.Results Eight RCTs were included (N = 1682). Although some individual studies showed positive effects to enhance meaning using mindfulness or dignity therapy, the overall and individual meta-analyses showed a lack of effect of psychological and spiritual interventions in comparison to comparator interventions (MD (95%CI) = -0.19 (-0.45 to 0.06), p = 0.11, Tau(2 )= 0.0015, I-2 = 2%). Publication bias was undetected (Egger's test = 0.35). Furthermore, no RCTs were judged to have a low risk of bias and the overall certainty of the evidence was judged as low. Meta-regression and subgroups meta-analyses also found possible sources of heterogeneity such as some cancer characteristics, the educational stage, or the religious affiliation.Conclusions Despite some RCTs may show promising results following mindfulness or dignity therapy, no effects were observed in the meta-analysis. Moreover, important methodological and clinical concerns precluded us to make sound clinical recommendations with the available evidence.