Forty one RCTs (n=4,884) were included in the review: 24 RCTs evaluated psychological interventions and 17 RCTs evaluated activity-based interventions. Thirty studies (n=3,443) had sufficient data and were included in the meta-analysis. Three RCTs were rated good, 31 fair and seven poor on the validity scale.
Nine (50%) of psychological trials and seven (44%) of activity based trials rated fair or good in quality had significant findings favouring the intervention condition.
An overall effect was found favouring psychological and activity based interventions combined compared to control (effect size of 0.09, 95% CI: 0.02 to 0.16, p<0.05; 30 studies). When separated into intervention modality, results were statistically significant for psychological interventions (effect size of 0.10, 95% CI: 0.02 to 0.18, p<0.05; 18 RCTs), but not for activity based interventions.
Subgroup analysis of psychological interventions found there was a statistically significant decrease in fatigue (effect size 0.09; 95% CI: 0.02 to 0.17, p<0.05; 18 studies), but no significant differences between intervention and control groups for vigour. There was no statistically significant decrease in fatigue for breast cancer patients, but there was for other types of patients (effect size 0.13; 95% CI: 0.01 to 0.25, p<0.05; eight RCTs). Studies of group interventions found a statistically significant decrease in fatigue compared to control (effect size 0.15; 95% CI: 0.01 to 0.28, p<0.05; nine RCTs). No significant effect was found for individual interventions. Subgroup analyses found no statistically significant differences between intervention or control groups for cancer type nor intervention type for vigour.
Subgroup analysis of activity-based intervention studies found no statistically significant effect for cancer type nor intervention type for fatigue.