Modelling the impact of physical activity on public health: A review and critique

Abstract

Background While several reviews have assessed economic evaluations of physical activity in public health and, in most cases, found the interventions to be cost-effective, the validity of the conclusions reached depends on the appropriateness of the modelling methods used in the individual studies. Objective To provide an overview and critique of modelling approaches and key structural assumptions used in applied studies to estimate the impact of physical activity on health. Methods Electronic databases were systematically searched for relevant model-based economic evaluations. A thematic approach was used to assess the modelling studies. The critique determined the appropriateness of the modelling frameworks and plausibility of key structural assumptions. Results Twenty-five models were identified. Cohort models were most frequently used. High variability in the modelling of downstream diseases was found across studies analysing similar populations. Structural assumptions regarding the dynamics of change of physical activity were unrealistic in most cases. Heterogeneity was addressed in only a few studies, while health equity concerns were, at best, acknowledged by authors. Conclusions This literature is predominantly characterised by modelling approaches that may not adequately address the complexities associated with representing the physical activity behaviour-population health process. A consensus on how to model the impact of physical activity on public health and development of a reference model could help reduce these sources of uncertainty.

Results from Poland’s 2022 Report Card on Physical Activity for Children and Youth

“…The evidence-based knowledge of the influence of physical activity (PA) on individual health [ 1 ], as well as an understanding of its influence on public health [ 2 , 3 , 4 ] has grown of late. There is emerging evidence suggesting that participation in physical activity may provide benefits beyond physical health [ 5 ].…”

How much behaviour change is required for the investment in cycling infrastructure to be sustainable? A break-even analysis

“…To the best of our knowledge, this is the first break-even economic analysis of a cycling infrastructure investment and more broadly a physical activity promotion intervention [ 41 ]. An example of such type of assessment can be found within the obesity literature, where Bates et al (2022) estimated the maximum justifiable cost for a weight loss maintenance intervention for individuals at different BMI and type II diabetes risk [ 42 ].…”

Taking a local government perspective for economic evaluation of a population-level programme to promote exercise

“…communities versus city dwelling) 52 . However, this study provides one of the few worked examples on how to conduct a health economic analysis tailored to the decision makers' information needs, which has been often overlooked in economic evaluations [20][21][22] .…”

“…quality-adjusted life years) is greater than the budget spent to implement the intervention. While those studies have found the interventions to be costeffective in most cases 18 , such approaches have been called into question [20][21][22] .…”