Study, year & location | Study type, study period & intervention period | Nature of tax or subsidy | Outcome measure | Study population | Sample size | Outcome data source | Major findings | Other impacts | Peer reviewed | Study quality |
---|---|---|---|---|---|---|---|---|---|---|
Currie [31] 2008 California, USA | Interrupted time series | Standard FSP –monthly food vouchers for any foods up to $142 per households per month dependent on income | Median birth weight, % of low birth weight, fetal survival | Pregnant women | n = 4,864,673 | Data on FSP participation from annual state, | FSP had a statistically significant (p < 0.05) but very small effect on the probability of fetal survival in Los Angeles amongst whites only (0.01 % greater for infants between 1500 and 2000 grams), though no effect was seen in the state as a whole. | None recorded | No | Strong |
 | 1961–1974 Duration of prenatal Food Stamp Programme (FSP) participation. | Forecasts of participation by county. | Introduction of FSP did not have any effect on low birth weight. | |||||||
 | Individual birth records | |||||||||
Herman [40] 2008 Los Angeles, California USA | Controlled before and after study | Standard Special Supplemental Nutrition Programme Women, Infants, and Children (WIC) programme plus $10 voucher weekly for Fruit and Vegetables (F&V) at two sites: 1) local supermarket, 2) farmer’s market. | F&V intake | Low-income postpartum women | intervention 1, n = 168, intervention 2, n = 140; control n = 143 | WIC | Participants in the intervention sites increased consumption of F&V. The increase was sustained 6 months after the intervention was terminated (p < 0.001). | None recorded | Yes | Weak |
 | 2001 | Farmers market participants increased consumption of F&V by 1.4 servings per 100 kcal of consumed food (p < 0.001) from baseline to the end of intervention compared to the control group, and supermarket participants increased by 0.8 servings per 100 kcal (p = 0.02) | ||||||||
 | 6 months | |||||||||
Baum [41] 2012 USA | Longitudinal study | FSP on expectant mothers | Weight gained by expectant mothers during pregnancy | Low income expectant mothers | n = 709 | National Longitudinal Survey of Youth 1979 | Food Stamp Receipt (FSR) decreases the probability of gaining insufficient weight during pregnancy with FSR increasing pregnancy weight gain by 1.78 lb (p < 0.05). However, it does not result in pregnant mothers gaining too much weight | None recorded | Yes | Weak |
 | 1979–2002 | |||||||||
 | 23 years | |||||||||
Black [45] 2013 New South Wales, Australia | Before and after uncontrolled study | Weekly box of subsidized fruit and vegetables up to $60 linked to preventive health services (annual health assessment including dental and hearing check-ups, blood testing) and nutritional promotion | Change in the episode of illness, health service and emergency department attendances, antibiotic prescription, BMI | Low-income Aboriginal families with one or more children <17 years of age who were regular patients at the respective health services | n = 167 | Retrospective health records audit and health assessment from Aboriginal health services, local hospitals and any other nominated general practices | A significant decrease (p < 0.05) in oral antibiotics prescribed (−0.5 prescriptions/year; 95%CI, −0.8 to −0.2) during 12 months of participation in the programme compared with the 12 months before the programme. | None recorded | Yes | Weak |
 | 2008–2010 | No significant reduction of BMI. | ||||||||
 | 2 years | Significant increase (p < 0.05) in mean Haemoglobin level (3.1 g/L; 95 % CI, 1.4–4.8 g/L). |