Table 3.
Substantive Findings and Study Design for Natural and Quasi-Experiments Evaluating Changes to Diet/Nutrition
| Reference | Type of Intervention and Setting | Strength of Study Design | Study Design | Study Population and Size | Outcome, Timing and Method of Outcome Assessment | Direction (expected, unexpected, null) |
|---|---|---|---|---|---|---|
| Angell, 201259 | Policy: Trans fat ban in restaurants (City in U.S.) | + | Repeat cross-sectional, case only1 | 14,855 purchases made by adult restaurant customers | Change in mean grams of trans fat per purchase; 20 months post-intervention: Direct measurement (receipts) | Expected (reduction in mean trans fat per purchase following ban) |
| Auchincloss, 201330 | Policy: Nutrition labeling in restaurants (City in U.S.) | + | One-time cross-sectional with comparison group | 648 adult restaurant customers | Calories, saturated fat, carbohydrates, sodium per restaurant purchase; 19 months post-intervention; Direct measurement (receipts) | Expected (fewer calories, less saturated fat, and sodium purchased at restaurants with labeling) |
| Buttenheim, 201265 | Food Environment: Food voucher payment systems at farmers markets. (City in U.S.) | + | Repeat cross-sectional, case only | 48 months (time series) of customer sales from multiple vendors at a single farmer’s market | Farmers Market sales; 9 months post-intervention; Direct measurement (transactions) | Expected (increase in farmers market purchases) |
| Cradock, 201163 | Policy: School Nutrition. Sugar-sweetened beverages not allowed in vending or à la carte (City in U.S.) | ++ | Repeat cross-sectional with comparison group1 | 2,033 public high school students | Daily consumption of sugar-sweetened beverages; 20 months post-intervention; Self-report (survey) | Expected (declines in consumption of sugar-sweetened beverages after policy compared to national trends) |
| Cullen, 200664 | Policy: School Nutrition. Changes to snack bars and vending. (City in U.S.) | + | Repeat cross-sectional, case only | 2,790 middle school students at 3 middle schools. | Daily mean calories and other nutrients, servings of healthy and unhealthy foods and beverages; Outcome measurement overlapped with intervention; Direct measurement (transactions) | Mixed (Consumption of sugar-sweetened beverages declined but consumption of chips/candy from vending machines increased) |
| Cummins, 200566 | Food Environment: Supermarket in food desert. (City in Scotland) | +++ | Within person longitudinal with comparison group. | 412 households-men and women aged ≥16 living near and far from supermarket | Daily fruit and vegetable portions consumed; 10 months post-intervention; Self-report (survey) | Null (no change in fruit/vegetable consumption associated with supermarket) |
| Dumanovsky, 201133 | Policy: Nutrition labeling in restaurants (City in U.S.) | + | Repeat cross-sectional, case only | 15,798 adult restaurant customers | Calories in restaurant purchases; 9 months post-intervention; Direct measurement (receipts) | Mixed-Null for full sample (no change), expected for some chains (reduction in calories purchased post policy) |
| Elbel, 200934 | Policy: Nutrition labeling in restaurants (City in U.S.) | ++ | Repeat cross-sectional with comparison group1 | 1,156 adult fast food restaurant customers in low-income, minority communities | Calories, saturated fat, sodium, sugar content of restaurant purchases; 1 month post-intervention; Direct measurement (receipts) | Null (no change in calories purchased after policy) |
| Elbel, 201155 | Policy: Nutrition labeling in restaurants (City in U.S.) | ++ | Repeat cross-sectional with comparison group1 | 349 children/adolescent fast food customers | Calories, saturated fat, sodium, sugar content of restaurant purchases; 1 month post-intervention; Direct measurement (receipts) | Null (no change in calories purchased after policy) |
| Finkelstein, 201156 | Policy: Nutrition labeling in restaurants (City in U.S.) | ++ | Repeat cross-sectional with comparison group1 | Transactions from 14 chain restaurants | Average calories per restaurant transaction; 1 month post-intervention; Direct measurement (receipts) | Null (no difference in trends in calories per transaction between intervention and control) |
| Mendoza, 201060 | Policy: School Nutrition. Changes to all school food environments, including snack bars and vending. (State in U.S.) | + | Repeat cross-sectional, case only | 12,788 self-reported food records from middle school students at 3 schools | Energy density of student lunch (kcal/g); 12 months post-intervention; Self-report (survey) | Expected (reduction in energy density following policy) |
| Mullally, 201061 | Policy: School Nutrition. Sugar-sweetened beverage vending ban, broad set of recommendations to offer healthier meals. (Province in Canada) | + | Repeat cross-sectional, case only | 1,533 5th-6th grade children at 11 elementary schools | Proportion of students meeting recommendations for fruit, vegetable, and milk consumption, consuming <3 servings of low nutrient dense foods; 12 months post-intervention; Self-report (survey) | Expected (reduction in low nutrient dense foods, increase in meeting recommendations for fruit, vegetables, and milk after policy) |
| Odoms-Young, 201338 | Policy: Food voucher eligible foods. (National, U.S.) | ++ | Within-person longitudinal, case only 1 | 273 Hispanic and African American children aged 2–3 years old enrolled in WIC and their mothers | Mean daily servings of healthy foods, home availability of healthy foods; 6 months post-intervention; Self-report (survey) | Expected (increase in fruit and low-fat dairy consumption, increase in home healthy food availability) |
| Sadler, 201341 | Food Environment: Supermarket. (City in U.S.) | ++ | Repeat cross-sectional with comparison group | 352 adults who were the primary shopper for their household | Mean daily servings of fruits and vegetables; 10 months post-intervention; Self-report (survey) | Null (no impact of intervention on fruit/vegetable consumption) |
| Snelling, 201262 | Policy: School Nutrition. Standards for school lunches, reduce unhealthy food in vending machines. (National, U.S.) | + | Repeat cross-sectional, case only | Purchases from 17,819 students at 3 high schools | Change in calories and fat purchased by students; 12 months post-intervention; Direct measurement (transactions) | Expected (reduction in calories and fat purchased after policy) |
| Sutherland, 201057 | Food Environment: Nutrition labeling in supermarkets (Region in U.S.) | + | Repeat cross-sectional, case only | Purchases from 168 outlets of a Northeast supermarket chain | Percentage of purchases that were classified as healthy; 12 months post-intervention; Direct measurement (transactions) | Expected (increase in purchasing of foods and beverages of high nutritional quality after intervention) |
| Tandon, 201142 | Policy: Nutrition labeling in restaurants (City in U.S.) | +++ | Within person longitudinal with comparison group1 | 133 6–11 year old children and their parents | Average calories purchased; 2 months post-intervention; Direct measurement (receipts) | Null (no change in average calories purchased from before to after policy) |
| Vadiveloo, 201158 | Policy: Nutrition labeling in restaurants (City in U.S.) | ++ | Repeat cross-sectional with comparison group1 | 1,170 adult restaurant customers at 4 chain restaurants | Types of foods purchased and frequency of fast food consumption; 1 month post-intervention; Direct measurement (receipts) | Mixed-Overall null (no change in types of food purchased) but those who reported noticing/using labels consumed fast food less frequently |