Optimizing age-based targeting in ice cleat distribution programs for preventing winter fall injuries: a...

Fall injuries on ice and snow are a major public health problem in cold climates, placing a substantial seasonal burden on healthcare systems and affected individuals. To prevent such injuries, many Swedish municipalities have implemented programs that distribute ice cleats, typically restricted to adults aged ≥ 65. Evidence suggests these programs increase cleat use, reduce injuries, and are cost-effective. However, it remains unclear whether restricting distribution to older adults is more effective than broader or universal strategies. This study is the first to formally evaluate this question.

We developed a cohort simulation model combining elements of the local average treatment effects framework and the health belief model to evaluate the cost-effectiveness of alternative ice cleat distribution strategies across age thresholds. The model incorporates age-specific injury risks, compliance, costs, and quality-adjusted life year losses, using input from behavioral surveys, register data on ice-related fall injuries, and published literature. It is calibrated to outcomes from real-world distribution programs. Cost-effectiveness was assessed from a societal perspective, defining optimal thresholds as those maximizing net monetary benefit and acceptable thresholds as those with > 50% probability of being cost-effective compared to no distribution in probabilistic sensitivity analyses.

Our primary analysis identified ≥ 55 years as the optimal eligibility threshold (acceptable range: 42-72). Sensitivity analyses indicated that universal distribution may be acceptable if cleats are purchased restrictively and targeted to non-users, but it is unlikely to be optimal. When assuming short-lived behavior change (≤ 2 years) or valuing costs from a healthcare perspective only, no distribution was preferable.

Age-targeted ice cleat distribution appears more cost-effective than universal provision and preferable to no distribution, but current programs limited to older adults may be suboptimal. Extending eligibility to middle-aged adults could further improve cost-effectiveness from a societal perspective.