turkey (0.1 kg), bacon (kg), lean beef mince (kg), lamb leg (kg), chicken â whole ... pizza â frozen (0.3-0.45 kg), mash and sausage â fresh (1p), pasta chicken ...
Appendix Accessibility and Affordability of Supermarkets: Associations With the DASH Diet Mackenbach et al.
Appendix Appendix Methods - Characterization of supermarkets according to cost All supermarkets were classified into one of four economic tiers, based on a 101-item market basket. The market basket should reflect both health and unhealthy items and contain foods as used in the Fenland food frequency questionnaire. The purpose was for the market basket to provide between-supermarket heterogeneity in food prices. A number of food lists were used as input for the construction of the market basket: the EPIC FFQ food groups (on which the Fenland FFQ was based); the food groups from the ‘eat well’ plate1; the 10 major food groups according to the European Food Safety Authority (EFSA)2; nutrients and foods with established relationship to health (EFSA); seven foods common in the European food-based-dietary guidelines3; food groups in the Centre for Public Health Nutrition (CPHN) market basket45; food items in the UK CPI market basket6. On the basis of these lists we chose 101 items, which were categorized into the following 11 food groups: fruits, vegetables, fat, dairy, breads/cereals, rice/pasta/potatoes, fish, meat, sugars and sweets, beverages and ‘other’. Amounts/units per item were chosen based on the UK CPI market basket. Data were collected on each item in the market basket in each of the seven supermarket chains in the area between December 2013 and January 2014 via www.mysupermarket.co.uk (an online price comparison website for UK supermarkets). The locations of all geocoded supermarkets in the study area are shown in Appendix Figure 1. Prices for Morrison’s were collected in-store. If not all supermarkets sold all products, we imputed missing values using mean imputation. We then compared the total price of the market basket as well as the price of items in the 12 food groups were compared between supermarket chains. We performed General Linear Model (GLM) repeated measures analysis to examine whether the price of the market basket was different between the seven supermarket chains. We used pairwise comparisons to examine which supermarket chains significantly differed in average market basket price. We additionally tested whether the prices of food items within food groups differed by supermarket brand using interaction terms between supermarket brand and food group. Analyses were conducted using SPSS version 22. In Appendix Table 1 we present the description of market basket food items (with their units) by food category, and their prices for each of the seven supermarket chains. Not all products were available in all supermarkets, such that only 73 items were available in all seven supermarket chains. Missing values were therefore imputed. The cost of the 101-item market basket of the most expensive supermarket (Co-Op; £355) was approximately £132 1
Appendix Accessibility and Affordability of Supermarkets: Associations With the DASH Diet Mackenbach et al.
more expensive than of the cheapest supermarket (Aldi; £223). General Linear Model (GLM) repeated measures analysis confirmed that the prices of 101 food items were different between the seven supermarket chains (Lower-bound F=15.03, p28. Coefficients were derived from logistic regression analyses. Boldface indicates statistical significance (p13 years of education Car ownership Energy intake (kcal) Presence of other food outlets Economic access to supermarkets T1 (ref; 0-2.03 km) T2 (2.04-7.35 km) T3 (7.36-32.16 km) Age Sex Education ≤11 years of education 12-13 years of education >13 years of education Car ownership Energy intake (kcal)
Model 1 OR 95%CI 1 0.83 0.76
0.73; 0.94 0.66; 0.86
Model 2 OR 1 0.93 0.81 1.03 2.30 0.44 0.60 0.84 1.00
1 0.67 0.53
0.59; 0.76 0.46; 0.60
1 0.71 0.57 1.03 2.24 0.45 0.63 0.90 1.00
95%CI
Model 3 OR
95%CI
0.82; 1.07 0.71; 0.93 1.02; 1.04 2.05; 2.57
1 0.96 0.85 1.03 2.30
0.84; 1.10 0.74; 0.98 1.02; 1.04 2.05; 2.58
0.37; 0.51 0.54; 0.68
0.45 0.62
0.38; 0.53 0.55; 0.70
0.68; 1.04 1.00; 1.00
0.87 1.00 1.00
0.70; 1.08 1.00; 1.00 1.00; 1.00
0.63; 0.81 0.50; 0.66 1.02; 1.04 2.00; 2.52
1 0.73 0.59 1.03 2.28
0.64; 0.83 0.52; 0.68 1.02; 1.04 2.03; 2.56
0.39; 0.53 0.56; 0.71
0.47 0.64
0.40; 0.55 0.57; 0.72
0.73; 1.12 1.00; 1.00
0.92 1.00
0.74; 1.14 1.00; 1.00 7
American Journal of Preventive Medicine
Appendix Accessibility and Affordability of Supermarkets: Associations With the DASH Diet Mackenbach et al.
Presence of other food outlets
1.00
1.00; 1.00
DASH, Dietary Approaches to Stop Hypertension. Accordance to DASH was defined as a DASH score >28. Coefficients were derived from logistic regression analyses. Boldface indicates statistical significance (p
