Jacobsen, P. B., Donovan, K. A., Vadaparampil, S. T., & Small, B. J. (2007). Systematic review and meta-analysis of psychological and activity-based interventions for cancer-related fatigue. Health Psychology, 26, 660–667.

Databases searched were PsycINFO, MEDLINE, and CINAHL through November 2005.

Seventeen randomized, controlled trials of activity-based interventions were included in the meta-analysis. Activity-based interventions included professionally supervised programs and unsupervised, home-based programs designed to promote exercise activity. To be included, a trial must have included a controlled comparison arm with either a no treatment or placebo condition, must have been a study of an activity-based intervention in adults diagnosed with cancer, one of the study outcomes must have been fatigue or the related constructs of vitality or vigor, and the reported results must have included significant testing of differences between an intervention condition and a control condition.

In all 17 studies in which fatigue, vitality, or vigor was assessed as an outcome, more than three-quarters of the studies measured the construct of fatigue. Fatigue, vitality, or vigor was a primary outcome in slightly more than half of all the studies of activity-based interventions, and it was a secondary outcome in the remainder. Activity-based interventions included professionally supervised programs and unsupervised, home-based programs designed to promote exercise activity. There were numerous differences across these studies in the type of exercise (e.g., aerobic or resistance), mode (e.g., walking or cycle ergometer), and intensity of exercise.

Sixteen of the 17 studies used no intervention control groups or wait-list control groups, and one study used a placebo control condition that involved stretching exercises. Sixty-one percent of the studies provided a home-based exercise intervention and 39% provided supervised exercise programs. No study specified the levels of fatigue, vigor, or vitality used as the eligibility criterion.

• Ten of the 17 trials were in patients with breast cancer only.
• Eleven studies included patients undergoing or about to start chemotherapy and/or radiotherapy, and five included only patients who had completed treatment.
• With regard to disease severity, 10 studies included only patients with nonmetastatic disease, and the remaining studies either did not specify metastatic status or were not restricted in terms of metastatic status.
• The total sample size for each activity-based intervention study ranged from 14 to 155 patients (median = 50 patients).

The effect size for activity-based interventions was not statistically significant (d_w = 0.05; 95% confidence interval [CI] [-0.08, -0.19]), and there were no differences in effect sizes as a function of cancer type (breast cancer:  d_w = 0.12; 95% CI [-0.15, -0.30]) or for all other types (d_w = 0.06; 95% CI [-0.11, -0.24]) or intervention modality (home-based:  d_w = 0.04; 95% CI [-0.13, -0.22]; supervised:  d_w = 0.16; 95% CI [-0.09, -0.41]).

• As with all meta-analyses of exercise that pool results across studies, there was variability in the type, mode, and intensity of exercise, as well as variation in the duration of the intervention and whether the intervention was supervised or home-based.
• Few studies provided an analysis of adherence effects in the intervention group, and no study reviewed by the authors required study participants to have a clinically significant level of fatigue. As a result, the possibility exists that many participants were experiencing little or no fatigue at the time of study entry, thus limiting the ability of these study designs to detect intervention effects.

The current results conflict with the results and conclusions made by other authors who conducted narrative systematic reviews of single studies, with meta-analyses that included both randomized and nonrandomized trials, and with the results of another meta-analysis published more recently. Close comparison of the studies reviewed by the current authors with those reviewed by Cramp and Daniel suggest that the conclusions were different in part because different randomized, controlled trials were examined. Six randomized, controlled trials of activity-based interventions with favorable effects on the outcome of cancer-related fatigue were published after the current authors completed their electronic database searches. In addition, the search strategies used by the current authors excluded two randomized, controlled trials that reported activity interventions (Galantino 2003; Dimeo 2004) that met the criteria for inclusion in their meta-analysis. Moreover, a meta-analysis published in April 2008 by the Cochrane Collaboration that included these more recently published trials together with the two trials that were inadvertently excluded by the current authors concluded that there was a small but statistically significant effect for exercise (standardized mean difference = -0.23; 95% CI [-0.33, -0.13]).