Smallest worthwhile effect of exercise programs to prevent falls among older people: Estimates from benefit-harm trade-off and discrete choice methods

Abstract

Background: the smallest worthwhile effect (SWE) of an intervention is the smallest treatment effect that justifies the costs, risks and inconveniences associated with that health intervention. Objective: to estimate the SWE of exercise programs designed to prevent falls among older people and to compare estimates derived by two methodological approaches. Study design and setting: discrete choice experiment (n = 220) and benefit-harm trade-off (subsample n = 66) methods were used. Participants: community-dwelling older people who reported a past fall or a mobility limitation answered online or face-to-face questionnaires. Results: a substantial proportion of participants (82% in the discrete choice experiment and 50% in the benefit-harm trade-off study) did not consider that participation in the proposed exercise programs would be worthwhile, even if it reduced their risk of falling to 0%. Among remaining participants, the average SWE of participation in an exercise program was an absolute reduction in the risk of falling of 35% (standard deviation [SD] = 13) in the discrete choice experiment and 16% (SD = 11) in the benefit-harm trade-off study. Conclusions: many participants did not consider the hypothetical falls' risk reduction of the proposed exercise programs to be worth the associated costs and inconveniences. Greater community awareness of the fall prevention effects of exercise for older people is required.