Table 1.
Grading of evidence.
| Risk factor | Intervention | Summary of evidence | Grade |
|---|---|---|---|
| Tobacco smoking | (T1) Increase excise taxes and prices on tobacco products | Consistent evidence from across several reviews | High |
| (T2) Implement plain/standardized packaging and/or large graphic health warnings on all tobacco packages | Consistent evidence from across several reviews | High | |
| (T3) Enact and enforce comprehensive bans on tobacco advertising, promotion and sponsorship | Consistent evidence from across several reviews and articles | High | |
| (T4) Eliminate exposure to second-hand tobacco smoke in all indoor workplaces, public places, public transport | Consistent evidence across several publications/reviews, from HICs and LMICs | High | |
| (T5) Establish and enforce an appropriate minimum age for purchase or consumption of tobacco | A 2005 Cochrane review demonstrates effective policies for enforcement of these policies, rather than the direct effect of implementation of the policy itself | Low | |
| Excess alcohol | (A1) Increase excise taxes on alcoholic beverages | Price elasticity values consistent across HIC and LMICs (in spite of less relative affordability in LMICs) | High |
| (A2) Establish minimum prices for alcohol where applicable | Consistent empirical evidence from two countries, confirming extensive previous supporting evidence | High | |
| (A3) Enact and enforce bans or comprehensive restrictions on exposure to alcohol advertising (across multiple types of media) - including in connection with sponsorships and activities targeting young people | Some empirical evidence demonstrating reductions in consumption resulting from restrictions, supported by extensive empirical and experimental evidence that increased marketing (including web-based marketing) increases attitudes and consumption. Evidence base is still maturing with respect to the specifics of the regulatory approach, and accurately estimating the potential impact, in the context of the changing global, web-based alcohol advertising landscape | Moderate | |
| (A4) Enact and enforce restrictions on the physical availability of retailed alcohol (via reduced hours of sale) | Limited empirical evidence presented by WHO, with no supporting Cochrane review. Supported by theoretical evidence, and empirical evidence from tobacco reduction, that availability is an important factor | Moderate | |
| (A5) Provide consumer information about, and label, alcoholic beverages to indicate, the harm related to alcohol | The totality of evidence points to a null, or very small effect, on drinking behaviour. It is possible that newer packaging designs could be more effective than previous designs, but more evidence is needed to confirm this | Low | |
| (A6) Enact and enforce an appropriate minimum age for purchase or consumption of alcoholic beverages and reduce density of retail outlets | There is limited empirical evidence for this recommendation. However, it is logical that an effectively enforced minimum legal drinking age does reduce the availability of alcohol to younger people | Low | |
| Obesity | (O1) Use effective taxation measures to reduce consumption of unhealthy products such as sugar-sweetened beverages | Consistent evidence across several reviews | High |
| (O2) Implement policies to protect children from the harmful impact of food marketing | Clear that comprehensive marketing bans could reduce consumption of unhealthy foods, but unclear applicability of current evidence base to broad population context. Supporting evidence from a systematic review of 44 natural experiment studies of restricting advertising to children (across a range of mediums), but the authors consider the overall quality of the evidence to be low. Comprehensive evidence base demonstrating the effectiveness of marketing to change children's preferences, but more real-world evidence is required to accurately ascertain the empirical effect of comprehensive marketing restrictions | Moderate | |
| (O3) Introduce menu labelling in food service to promote healthy diets (e.g., reduce total energy intake (kcal) and/or intake of sugars) | A Cochrane review summarizes the emerging evidence base, with meta-analysis of empirical studies supported by similar findings from experimental evidence | Moderate | |
| (O4) Limiting portion and package size to reduce energy intake and the risk of overweight/obesity | Evidence from a meta-analysis of RCT evidence - including real-world studies | High | |
| (O5) Public food procurement and service policies for healthy diets (e.g., to reduce the intake of free sugars, and to increase the consumption of legumes, wholegrains, fruits and vegetables) | Evidence from several reviews supports school-based policies for ensuring that food provided/available is healthy. This is supported by evidence from other reviews demonstrating successful programmes in other settings. Heterogeneity in intervention design and variable study quality is a feature of this evidence base, with few studies including appropriate control groups, and studies generally not capturing any effects of the policies on food consumed outside of the setting. However, there is a strong argument for these interventions to be included, alongside other diet-based policies, to improve the overall food environment | Moderate | |
| (O6) Reformulation policies for healthier food and beverage products (e.g., reduction of free sugars) | Evidence from several reviews demonstrating reformulation policies can be effective. Range of effect sizes reflects heterogeneity in reformulation policies adopted for various populations and food products. Consistent evidence that mandatory policies more effective than those reliant on voluntary action or industry self-regulation | High | |
| (O7) Subsidies on healthy foods and beverages (e.g., fruits and vegetables) as part of comprehensive fiscal policies for healthy diets | Consistent evidence across several reviews show effectiveness for increasing healthy food consumption, but outcomes such as total caloric intake not reported | Low | |
| (O8) Front-of-pack labelling as part of comprehensive nutrition labelling policies for facilitating consumers' understanding and choice of food for healthy diets | Empirical evidence base for effectiveness is fairly weak with the majority of evidence coming from modelling studies or evidence using self-report and examining consumer understanding and attitudes in response to FOPL. However, emerging evidence base suggesting that FOPL can also contribute to reformulation drives. Based on totality of evidence, likely that FOPL will produce small effects, if any, but could be a contributory policy to support other changes to the food environment and marketing | Low | |
| Physical Inactivity | (P1) Implement urban and transport planning and design, at all levels of government, to provide compact neighbourhoods providing mixed-land use and connected networks for walking and cycling and equitable access to safe, quality public open spaces that enable and promote physical activity and active mobility (including wheelchairs, scooters and skates) by people of all ages and abilities | Clear empirical and supporting evidence that changes to urban design can increase physical activity rates through increased walking and cycling. However, no meta-analysis reported, and several studies reported null results, reflecting a maturing evidence base. Uncertainty regarding the potential magnitude of effect, potential waning/increasing over time, and overall effect on physical inactivity prevalence and obesity | Moderate |
| (P2) Implement whole-of-school programmes that include quality physical education, and adequate facilities, equipment and programs supporting active travel to/from school and support physical activity for all children of all abilities during and after school | The totality of evidence suggests the potential for a small effect on total physical activity. Much of the evidence-base consists of multi-component interventions which generally include approaches like health education and curricular changes to increase the amount of physical activity conducted at school, but do not generally tackle broader structural issues such as the built environment outside of school and gender norms. However, it is logical that policies to integrate active school travel and exercise during the school day could be complimentary to a broader strategy, and there is evidence that some interventions can contribute to increased physical activity and be acceptable to large proportions of participants | Low | |
| (P3) Implement multi-component workplace physical activity programmes | Limited empirical evidence for population-level interventions. As for school-based interventions, it is logical that workplaces could be important partners in broader approaches to make physical activity easier, such as providing shower facilities for employees. Other possible interventions, such as flexible working hours to allow for active commuting in daylight, were not identified in any cited documents | Low | |
| Hypertension | (H1) Public food procurement and service policies to reduce the intake of sodium | Evidence from several reviews supports school-based policies for ensuring that food provided/available is healthy. This is supported by evidence from other reviews demonstrating successful programmes in other settings. Heterogeneity in intervention design and variable study quality is a feature of this evidence base, with few studies including appropriate control groups, and studies generally not capturing any effects of the policies on food consumed outside of the setting. However, there is a strong argument for these interventions to be included, alongside other diet-based policies, to improve the overall food environment | Moderate |
| (H2) Reformulation policies for reduction of sodium content | Evidence from several reviews demonstrating reformulation policies can be effective. Range of effect sizes reflects heterogeneity in reformulation policies adopted for various populations and food products. Consistent evidence that mandatory policies more effective than those reliant on voluntary action or industry self-regulation | High | |
| Depression | (D1) Interventions to improve the social determinants of health, including social security policies, housing improvements, and community wealth building | Some evidence that these interventions can reduce depression, but insufficient consistency to be confident in the factors which drive a successful, rather than null, outcome. One study demonstrated a reduction in anti-depressant prescribing (objectively, using electronic health records) in a deprived area of the UK, following introduction of a community wealth building (CWB) programme which involved working with local anchor institutions to address upstream economic inequalities through measures like equitable distribution of investments and procurement, and commitment to paying a ‘living wage’ to all employees, which may demonstrate an evolving evidence base | Low |
| Traumatic Brain Injury | (Tr1) Mandate the use of motorcycle helmets (all aged passengers) | Clear evidence from a systematic review reported by WHO, reporting studies from the US showing reductions in head injuries and hospitalisation amongst children after policy introduction. Further supportive evidence from WHO and Cochrane, including from LMICs | Moderate |
| (Tr2) Mandate the use of bicycle helmets (children) | Clear evidence from a Cochrane review reporting studies from the US and Canada showing reductions in head injuries and hospitalisation after policy introduction. Further supportive evidence from WHO | Moderate | |
| (Tr3) Provision of free bicycle helmets to children aged under 12 | Included as a component in several multi-component interventions reported by WHO and Cochrane | Low | |
| Low Educational Attainment | (E1) Provide financial support (including removing school fees, conditional payments to schools, conditional cash transfers to households) for children to attend school, where financial barriers would otherwise exist | Campbell collaboration review reported direct evidence from 7 studies (free primary schools in Uganda n = 3 studies, studies of primary school tuition waivers (e.g., via conditional payments to the school) n = 3 from Haiti, Pakistan, Ecuador, and secondary school tuition waivers n = 1 from Ghana, supported by 10 further studies which were multi-component but included free schooling) | Moderate |
| (E2) Provide free lunches in primary schools, where a lack of adequate food would otherwise be a barrier to school attendance | Campbell collaboration review reported two studies reported effects on boys and girls combined. One examined the effects of policies to improve access and quality of schooling in Burkina Faso, using secondary data from surveys and RCTs, reporting significant benefits, mainly for in-school feeding programmes and also out of school rations in some cases. Another considered the effect of a national policy to provide free lunches to all primary school children in India and reported significant benefits to primary school enrolment. Supportive evidence from ten studies reported effects on girls specifically | Moderate | |
| (E3) Raise the mandatory school leavers age in HICs | Report for the European Commission on Economic Policy reported that expanding compulsory education ages statistically significantly increased educational attainment, and had equity benefits. Supported by several references to other reviews of empirical data which each find increases in attainment associated with later compulsory leaving age, and equity effects | High | |
| (E4) Provide school materials, where there would otherwise be difficulty in affording and obtaining these | Campbell collaboration review reported similar results to those for adequate food, with 2 studies reporting benefits when effects are combined for boys and girls, and a more mixed picture for girls alone. However, the evidence quality was more mixed, the interventions were more heterogeneous, and the majority of evidence was from multi-component interventions (e.g., combined uniform provision with support for tuition fees) | Low | |
| (E5) Improve geographical access to schools | Campbell collaboration review reported that interventions to address inadequate access to school were consistently effective, but the authors were unable to disentangle the specific effects of these interventions from the multi-component programmes they were part of | Low | |
| (E6) Improve water supply and sanitation in schools | Campbell collaboration review reported that interventions to address water and sanitation in schools were consistently effective, but the authors were unable to disentangle the specific effects of these interventions from the multi-component programmes they were part of | Low | |
| Air Pollution | (Ai1) Replacement and maintenance programmes providing cleaner cooking stoves for those currently using biomass fuels on traditional stoves or open fire | Clear evidence from several RCTs, but no systematic review, that this can reduce kitchen PM2.5 and CO. Limited data from the use of individual air pollution monitors. Supported by a systematic review of qualitative evidence to understand predictors of success | Moderate |
| (Ai2) Urban interventions to reduce density of traffic, including: low emission zones, even-odd restrictions on cars | Clear evidence from studies reported by Cochrane review that these restrictions reduce PM2.5, PM10, NO and CO, in both summer and winter conditions | Moderate | |
| (Ai3) Postponement of non-essential polluting activities on high-pollution days | Clear evidence from studies reported by Cochrane review that these restrictions reduce PM10 and cardiovascular hospitalisations | Moderate | |
| (Ai4) Comprehensive (marketing, sale and distribution) coal bans for residential heating | Cochrane review presents evidence from one country (Ireland) that this can reduce respiratory and cardiovascular hospitalisations and mortality, but no empirical evidence of the associated reduction in pollution | Low | |
| Hearing Impairment | (He1) Worksites exceeding recognised noise thresholds should reduce noise through improving equipment where feasible, and should provide and mandate the use of adequate hearing protection, with regular monitoring | Clear evidence from a Cochrane review that occupational policies to monitor and reduce noise exposure, and to provide, and mandate the use of, adequate hearing protection, can reduce acquisition of short- and longer-term hearing impairment | Moderate |
HICs = High income countries. LMICs = Low- and middle-income countries. WHO = World Health Organization. RCT = Randomised Controlled Trials. FOPL = Front of pack labelling. PM = Particulate matter. CO = Carbon monoxide. NO = Nitrous Oxide.