Abstract
BACKGROUND: Volunteers are increasingly promoted to improve health-related outcomes for community-dwelling elderly without synthesized evidence for effectiveness. This systematic review and meta-analysis evaluates the effects of unpaid volunteer interventions on health-related outcomes for such seniors. METHODS: MEDLINE, EMBASE and Cochrane (CENTRAL) were searched up to November 2018. We included English language, randomized trials. Two reviewers independently identified studies, extracted data, and assessed evidence certainty (using GRADE). Meta-analysis used random-effects models. Univariate meta-regressions investigated the relationship between volunteer intervention effects and trial participant age, percentage females, and risk of bias. RESULTS: 28 included studies focussed on seniors with a variety of chronic conditions (e.g., dementia, diabetes) and health states (e.g., frail, palliative). Volunteers provided a range of roles (e.g., counsellors, educators and coaches). Low certainty evidence found that volunteers may improve both physical function (MD = 3.2 points on the 100-point SF-36 physical component score [PCS]; 95% CI: 1.09, 5.27) and physical activity levels (SMD = 0.5, 95% CI: 0.14 to 0.83). Adverse events were not increased. CONCLUSION: Volunteers may increase physical activity levels and subjective ratings of physical function for seniors without apparent harm. These findings support the WHO call to action on evidence-based policies to align health systems in support of older adults.