Non-pharmacologic interventions for improving cancer-related fatigue (CRF): A systematic review of systematic reviews and pooled meta-analysis

Introduction: Literature encloses numerous systematic reviews (SRs) on nonpharmacologic interventions for improving cancer-related fatigue (CRF). The effect of these interventions remains controversial, and the available SRs have not been synthesized yet. We conducted a systematic synthesis of SRs and meta-analysis to determine the effect of nonpharmacologic interventions on CRF in adults. Material and methods: We systematically searched 4 databases. The effect sizes (standard mean difference) were quantitatively pooled using a random-effects model. Chi-squared (Q) and I-square statistics (I²) tested the heterogeneity. Results: We selected 28 SRs, including 35 eligible meta-analyses. The pooled effect size (standard mean difference, 95% CI) was -0.67 (-1.16, -0.18). The subgroup analysis by types of interventions showed a significant effect in all the investigated approaches (complementary integrative medicine, physical exercise, self-management/e-health interventions). Conclusions: There is evidence that nonpharmacologic interventions are associated with CRF reduction. Future research should focus on testing these interventions on specific population clusters and trajectories. Prospero registration: CRD42020194258.