Steven Cummins

“Food deserts”—evidence and assumption in health policy making

Assertions can be reported so often that they are considered true (“factoids”). They may sometimes even be used to determine health policy when empirical information is lacking. Steven Cummins and Sally Macintyre use the claimed existence of “food deserts”—poor urban areas where residents cannot buy affordable, healthy food—to illustrate why policy makers need to look more critically at the facts In December 2001 a cross party motion on food poverty signed by 198 UK MPs gained its first reading in parliament. The Food Poverty (Eradication) Bill is now waiting to be read for a second time.1 Though this bill is a laudable attempt to introduce a policy designed to improve the nutrition of those with the lowest incomes and in the poorest places, it is an example of how some ideas become accepted as fact though they may not be true. They become “factoids”: assumptions or speculations reported and repeated so often that they are popularly considered true; they are simulated or imagined facts.2 This paper illustrates how, if the social climate is right, facts about the social world can be assumed and hence used as the basis for health policy in the absence of much empirical information. ### Summary points Factoids are assumptions or speculations reported and repeated until they are considered true They are sometimes used to determine health policy when empirical information is lacking The assumption that in the United Kingdom there are poor urban areas where residents cannot buy affordable, healthy food (“food deserts”) is a factoid Policy strategies to combat the existence of food deserts exemplify how factoids can influence health and social policy The burden of proof, or demand for evidence, may vary according to a policys perceived fit within current collective world views Policy makers need to move away from unquestioning acceptance and should …

Large scale food retailing as an intervention for diet and health: quasi-experimental evaluation of a natural experiment

Objectives: To assess the effect on fruit and vegetable consumption, self reported, and psychological health of a “natural experiment”—the introduction of large scale food retailing in a deprived Scottish community. Design: Prospective quasi-experimental design comparing baseline and follow up data in an “intervention” community with a matched “comparison” community in Glasgow, UK. Participants: 412 men and women aged 16 or over for whom follow up data on fruit and vegetable consumption and GHQ-12 were available. Main outcome measures: Fruit and vegetable consumption in portions per day, poor self reported health, and poor psychological health (GHQ-12). Main results: Adjusting for age, sex, educational attainment, and employment status there was no population impact on daily fruit and vegetable consumption, self reported, and psychological health. There was some evidence for a net reduction in the prevalence of poor psychological health for residents who directly engaged with the intervention. Conclusions: Government policy has advocated using large scale food retailing as a social intervention to improve diet and health in poor communities. In contrast with a previous uncontrolled study this study did not find evidence for a net intervention effect on fruit and vegetable consumption, although there was evidence for an improvement in psychological health for those who directly engaged with the intervention. Although definitive conclusions about the effect of large scale retailing on diet and health in deprived communities cannot be drawn from non-randomised controlled study designs, evaluations of the impacts of natural experiments may offer the best opportunity to generate evidence about the health impacts of retail interventions in poor communities.

Neighbourhood environment and its association with self rated health: evidence from Scotland and England

Objectives: To investigate associations between measures of neighbourhood social and material environment and self rated health. Design: New contextual measures added to cross sectional study of a sample of people from the Health Survey for England and the Scottish Health Survey to provide multilevel data. Participants: 13 899 men and women aged 16 or over for whom data on self rated health were available from the Health Survey for England (years 1994–99) and the Scottish Health Survey (years 1995 and 1998). Results: Fair to very bad self rated health was significantly associated with six neighbourhood attributes: poor physical quality residential environment, left wing political climate, low political engagement, high unemployment, lower access to private transport, and lower transport wealth. Associations were independent of sex, age, social class, and economic activity. Odds ratios were larger for non-employed residents than for employed residents. Self rated health was not significantly associated with five other neighbourhood measures: public recreation facilities, crime, health service provision, access to food shops, or access to banks and buildings societies. Conclusions: Some, but not all, features of the neighbourhood environment are associated with self rated health and may be indicators of important causal pathways that could provide a focus for public health intervention strategies. Associations were more pronounced for non-employed residents, perhaps because of greater exposure to the local environment compared with employed people. Operationalising specific measures of the characteristics of local areas hypothesised to be important for living a healthy life provides a more focused approach than general measures of deprivation in the search for area effects.

Crime, fear of crime, environment, and mental health and wellbeing: Mapping review of theories and causal pathways

This paper presents the findings from a review of the theoretical and empirical literature on the links between crime and fear of crime, the social and built environment, and health and wellbeing. A pragmatic approach was employed, with iterative stages of searching and synthesis. This produced a holistic causal framework of pathways to guide future research. The framework emphasises that crime and fear of crime may have substantial impacts on wellbeing, but the pathways are often highly indirect, mediated by environmental factors, difficult to disentangle and not always in the expected direction. The built environment, for example, may affect health via its impacts on health behaviours; via its effects on crime and fear of crime; or via the social environment. The framework also helps to identify unexpected factors which may affect intervention success, such as the risk of adverse effects from crime prevention interventions as a result of raising awareness of crime.

The location of food stores in urban areas: a case study in Glasgow

During the late 1990s there has been an increasing interest in the concept of “food deserts” (populated areas with little or no food retail provision). It has been suggested that they are more likely to be found in deprived areas; however there has been little systematic research on their prevalence and distribution. This paper describes a preliminary analysis of the location of food outlets in the Greater Glasgow Health Board Area. Data were collected as part of a project on spatial variations in the price and availability of food. Based on all 79 multiple stores, and a 1 in 9 sample (n = 246) of all non‐multiple stores in the area, we did not find any evidence for the existence of food deserts, and found that food stores were more numerous in the more deprived localities and postcode districts in the study site.

Interrupted time series regression for the evaluation of public health interventions: a tutorial

Abstract Interrupted time series (ITS) analysis is a valuable study design for evaluating the effectiveness of population-level health interventions that have been implemented at a clearly defined point in time. It is increasingly being used to evaluate the effectiveness of interventions ranging from clinical therapy to national public health legislation. Whereas the design shares many properties of regression-based approaches in other epidemiological studies, there are a range of unique features of time series data that require additional methodological considerations. In this tutorial we use a worked example to demonstrate a robust approach to ITS analysis using segmented regression. We begin by describing the design and considering when ITS is an appropriate design choice. We then discuss the essential, yet often omitted, step of proposing the impact model a priori. Subsequently, we demonstrate the approach to statistical analysis including the main segmented regression model. Finally we describe the main methodological issues associated with ITS analysis: over-dispersion of time series data, autocorrelation, adjusting for seasonal trends and controlling for time-varying confounders, and we also outline some of the more complex design adaptations that can be used to strengthen the basic ITS design.

An open letter to The BMJ editors on qualitative research

Seventy six senior academics from 11 countries invite The BMJ ’s editors to reconsider their policy of rejecting qualitative research on the grounds of low priority. They challenge the journal to develop a proactive, scholarly, and pluralist approach to research that aligns with its stated mission

Diet And Perceptions Change With Supermarket Introduction In A Food Desert, But Not Because Of Supermarket Use

Placing full-service supermarkets in food deserts--areas with limited access to healthy food--has been promoted as a way to reduce inequalities in access to healthy food, improve diet, and reduce the risk of obesity. However, previous studies provide scant evidence of such impacts. We surveyed households in two Pittsburgh, Pennsylvania, neighborhoods in 2011 and 2014, one of which received a new supermarket in 2013. Comparing trends in the two neighborhoods, we obtained evidence of multiple positive impacts from new supermarket placement. In the new supermarket neighborhood we found net positive changes in overall dietary quality; average daily intakes of kilocalories and added sugars; and percentage of kilocalories from solid fats, added sugars, and alcohol. However, the only positive outcome in the recipient neighborhood specifically associated with regular use of the new supermarket was improved perceived access to healthy food. We did not observe differential improvement between the neighborhoods in fruit and vegetable intake, whole grain consumption, or body mass index. Incentivizing supermarkets to locate in food deserts is appropriate. However, efforts should proceed with caution, until the mechanisms by which the stores affect diet and their ability to influence weight status are better understood.

Variations in fresh fruit and vegetable quality by store type, urban–rural setting and neighbourhood deprivation in Scotland

OBJECTIVE Neighbourhood differences in access to fresh fruit and vegetables may explain social inequalities in diet. Investigations have focused on variations in cost and availability as barriers to the purchase and consumption of fresh produce; investigations of quality have been neglected. Here we investigate whether produce quality systematically varies by food store type, rural-urban location and neighbourhood deprivation in a selection of communities across Scotland. DESIGN Cross-sectional survey of twelve fresh fruit and vegetable items in 288 food stores in ten communities across Scotland. Communities were selected to reflect a range of urban-rural settings and a food retail census was conducted in each location. The quality of twelve fruit and vegetable items within each food store was evaluated. Data from the Scottish Executive were used to characterise each small area by deprivation and urban-rural classification. SETTING Scotland. RESULTS Quality of fruit and vegetables within the surveyed stores was high. Medium-sized stores, stores in small town and rural areas, and stores in more affluent areas tended to have the highest-quality fresh fruit and vegetables. Stores where food is secondary, stores in urban settings and stores in more deprived areas tended have the lowest-quality fresh produce. Although differences in quality were not always statistically significant, patterns were consistent for the majority of fruit and vegetable items. CONCLUSIONS The study provides evidence that variations in food quality may plausibly be a micro-environmental mediating variable in food purchase and consumption and help partially explain neighbourhood differences in food consumption patterns.

Associations between active commuting, body fat, and body mass index: population based, cross sectional study in the United Kingdom.

Objective To determine if promotion of active modes of travel is an effective strategy for obesity prevention by assessing whether active commuting (walking or cycling for all or part of the journey to work) is independently associated with objectively assessed biological markers of obesity. Design Cross sectional study of data from the wave 2 Health Assessment subsample of Understanding Society, the UK Household Longitudinal Study (UKHLS). The exposure of interest, commuting mode, was self reported and categorised as three categories: private transport, public transport, and active transport. Participants The analytic samples (7534 for body mass index (BMI) analysis, 7424 for percentage body fat analysis) were drawn from the representative subsample of wave 2 respondents of UKHLS who provided health assessment data (n=15 777). Main outcome measures Body mass index (weight (kg)/height (m)2); percentage body fat (measured by electrical impedance). Results Results from multivariate linear regression analyses suggest that, compared with using private transport, commuting by public or active transport modes was significantly and independently predictive of lower BMI for both men and women. In fully adjusted models, men who commuted via public or active modes had BMI scores 1.10 (95% CI 0.53 to 1.67) and 0.97 (0.40 to 1.55) points lower, respectively, than those who used private transport. Women who commuted via public or active modes had BMI scores 0.72 (0.06 to 1.37) and 0.87 (0.36 to 0.87) points lower, respectively, than those using private transport. Results for percentage body fat were similar in terms of magnitude, significance, and direction of effects. Conclusions Men and women who commuted to work by active and public modes of transport had significantly lower BMI and percentage body fat than their counterparts who used private transport. These associations were not attenuated by adjustment for a range of hypothesised confounding factors.