I’m curious why mass media campaigns would be the recommended action given that meta-analysis of mass media campaigns don’t seem indicate a reduction in sedentary behavior nor achievement of recommended physical activity levels, (though they do promote some increase in walking.) Lobbying to invest in the built environment seems cheaper and also more effective in the long run. Organizations like Strong Towns, Bloomberg City Labs, various walking and biking safety groups advocate/lobby for walkable neighborhood changes that are very affordable, if not free, like loosening zoning to allow for mixed-use buildings, multiple homes/businesses in one lot, reduced parking minimums. Many of the changes only require legislative change, since businesses or developers take on cost of new construction. Urban3 consultancy group has considerable research into the significantly higher tax revenues cities get from new residential and commercial developments, replacing underutilized spaces like parking lots. I would guess that influencing national health organizations (like national cancer or diabetes associations) to see walkable neighborhoods as possible could increase the pace of change. Other ways to get other groups to join the lobbying effort might be to clarify via mass media campaigns the link between car-centric infrastructure to the high rates of road fatalities (the main way to make roads safer is to build pedestrian/biking infrastructure (build buffers to remove “stroads”, bike lanes = narrow roads, sidewalk bump-outs = increase visibility, both of these decrease speeding). Or clarify the health impacts of children (developmental delays and asthma) for those who live on car-centric streets. I would guess these mass media campaigns would have a counterfactual difference (though indirectly to your goal) since road fatalitiy preventability and children health outcomes from even just proximity to cars are things people are not aware of, whereas almost everyone is aware that physical activity is good.
(1) On the evidence base for mass media interventions: Our choice to prioritize mass media (and so attempt more detailed modelling) was based on it (a) looking good in cost-effectiveness at a a shallower research stage with a less; (b) being recommended by the WHO as the most cost-effective intervention for promoting physical activity; and (c) generally, mass media interventions being 2nd only to policy in cheap scalability.
We relied on the study you cited (Abioye, Hajifathalian & Danaei), and took into consideration all three meta-analyses (impact on sedentary behaviour, sufficient walking, and sufficient physical activity), while discounting based on the degree to which measured outcome is dissimilar to GBD/WHO definitions of sufficient physical activity (>= 600 METs minutes per week). We did not exclude the sedentary meta-analysis results based on the fact that its reliant on a low quality outlier, but did perform our own analysis, to discount it (and the other meta-analyses) on the basis of underlying study quality (especially with respect to endogeneity) and publication bias.
We also considered whether the studies being from high-income countries biases the result (n.b. on the one hand, ageing high income countries are older and more sedentary, which implies a larger group of potential beneficiaries and greater population-level effect size; on the other hand, as Rosie Bettle of FP notes in her report on mass media interventions, its potentially the case that basic healthcare knowledge is more lacking in poorer countries, so you can—as with vaccine uptake—increase uptake there in a way).
Overall, we do think there’s is an effect, but it’s highly uncertain, and there’s a real chance it’s zero. For more details, see the ultra-long (and fairly tedious) discussion in this cell (Tractability:B12) of the CEA.
(2) Built environment changes: We did take a look at this option (seeAnnex A in our CEAfor a qualitative discussion of the available intervention options, and the relevant evidence base/expert feedback). We ultimately prioritized mass media (for reasons discussed above), but I do think such environment changes will be substantially more impactful but also much, much harder.
For one, if we’re talking about not just high-income countries but LMICs, the situation is very different. Zoning is justmuch less a factorthan in the rich world (they may not have much on the books, and what’s on the books may not be enforced), so the problem they face isn’t the one that the US/UK etc face and which YIMBYs are trying to solve. Their major cities are also extremely dense, and people havelow vehicle ownership rates(but worse congestion and air pollution). Making these cities more walkable isn’t just a matter of allowing dense housing, but spending a lot of money to improve public transport, solving air pollution etc, and that’s a fundamentally much harder ask for poor countries.
I’m curious why mass media campaigns would be the recommended action given that meta-analysis of mass media campaigns don’t seem indicate a reduction in sedentary behavior nor achievement of recommended physical activity levels, (though they do promote some increase in walking.) Lobbying to invest in the built environment seems cheaper and also more effective in the long run. Organizations like Strong Towns, Bloomberg City Labs, various walking and biking safety groups advocate/lobby for walkable neighborhood changes that are very affordable, if not free, like loosening zoning to allow for mixed-use buildings, multiple homes/businesses in one lot, reduced parking minimums. Many of the changes only require legislative change, since businesses or developers take on cost of new construction. Urban3 consultancy group has considerable research into the significantly higher tax revenues cities get from new residential and commercial developments, replacing underutilized spaces like parking lots. I would guess that influencing national health organizations (like national cancer or diabetes associations) to see walkable neighborhoods as possible could increase the pace of change. Other ways to get other groups to join the lobbying effort might be to clarify via mass media campaigns the link between car-centric infrastructure to the high rates of road fatalities (the main way to make roads safer is to build pedestrian/biking infrastructure (build buffers to remove “stroads”, bike lanes = narrow roads, sidewalk bump-outs = increase visibility, both of these decrease speeding). Or clarify the health impacts of children (developmental delays and asthma) for those who live on car-centric streets. I would guess these mass media campaigns would have a counterfactual difference (though indirectly to your goal) since road fatalitiy preventability and children health outcomes from even just proximity to cars are things people are not aware of, whereas almost everyone is aware that physical activity is good.
Thanks for the thoughtful comment!
(1) On the evidence base for mass media interventions: Our choice to prioritize mass media (and so attempt more detailed modelling) was based on it (a) looking good in cost-effectiveness at a a shallower research stage with a less; (b) being recommended by the WHO as the most cost-effective intervention for promoting physical activity; and (c) generally, mass media interventions being 2nd only to policy in cheap scalability.
We relied on the study you cited (Abioye, Hajifathalian & Danaei), and took into consideration all three meta-analyses (impact on sedentary behaviour, sufficient walking, and sufficient physical activity), while discounting based on the degree to which measured outcome is dissimilar to GBD/WHO definitions of sufficient physical activity (>= 600 METs minutes per week). We did not exclude the sedentary meta-analysis results based on the fact that its reliant on a low quality outlier, but did perform our own analysis, to discount it (and the other meta-analyses) on the basis of underlying study quality (especially with respect to endogeneity) and publication bias.
We also considered whether the studies being from high-income countries biases the result (n.b. on the one hand, ageing high income countries are older and more sedentary, which implies a larger group of potential beneficiaries and greater population-level effect size; on the other hand, as Rosie Bettle of FP notes in her report on mass media interventions, its potentially the case that basic healthcare knowledge is more lacking in poorer countries, so you can—as with vaccine uptake—increase uptake there in a way).
Overall, we do think there’s is an effect, but it’s highly uncertain, and there’s a real chance it’s zero. For more details, see the ultra-long (and fairly tedious) discussion in this cell (Tractability:B12) of the CEA.
(2) Built environment changes: We did take a look at this option (seeAnnex A in our CEA for a qualitative discussion of the available intervention options, and the relevant evidence base/expert feedback). We ultimately prioritized mass media (for reasons discussed above), but I do think such environment changes will be substantially more impactful but also much, much harder.
For one, if we’re talking about not just high-income countries but LMICs, the situation is very different. Zoning is just much less a factor than in the rich world (they may not have much on the books, and what’s on the books may not be enforced), so the problem they face isn’t the one that the US/UK etc face and which YIMBYs are trying to solve. Their major cities are also extremely dense, and people have low vehicle ownership rates (but worse congestion and air pollution). Making these cities more walkable isn’t just a matter of allowing dense housing, but spending a lot of money to improve public transport, solving air pollution etc, and that’s a fundamentally much harder ask for poor countries.