19. Food and nutrition subsidies – results of included prospective controlled studies.
| Study ID (risk of bias) | Study design (n) | Food rebate | No intervention | Effect measure (time point) | Effect directiona | ||||
| Results at baseline | Results at follow‐up | n | Results at baseline | Results at follow‐up | n | ||||
| Primary outcomes | |||||||||
| 5.2 Proportion of HH expenditure on food | |||||||||
| 5.2.1 Outcome measure: ratio of healthy to total food expenditure (mean, SD) | |||||||||
| Sturm 2013 – 10% rebate (‐) | Prospective controlled study (169,485 HHs) | 0.21 (0.11) | — | 67,343 HHs | 0.17 (0.13) | — | 69,141 HHs | Increase by 6.0%, 95% CI 5.3% to 6.8% (3 years) | ▲ |
| Sturm 2013 – 25% rebate (‐) | Prospective controlled study (136,484 HHs) | 0.21 (0.12) | — | — | 0.17 (0.13) | — | — | Increase by 9.3%, 95% CI 8.5% to 10.0% (2 years and 4 months) | ▲ |
| 5.4 Change in adequacy of dietary intake | |||||||||
| 5.4.1 Outcome measure: ratio of current caloric intake to the RDA (multiplied by 100) | |||||||||
| Andaleeb 2016 (‐) | Controlled before‐after study | NR | NR | 1134 HHs | NR | NR | NR | DID estimate 2.55, SE 1.31, 95% CI –0.018 to 5.118, P < 0.1 (7 years) | △ |
| 5.4.2 Outcome measure: ratio of current protein intake to the RDA (multiplied by 100) | |||||||||
| Andaleeb 2016 (‐) | Controlled before‐after study | NR | NR | 1134 HHs | NR | NR | NR | DID estimate 3.75, SE 1.65, 95% CI 0.516 to 6.984, P < 0.05 (7 years) | ▲ |
| 5.4.3 Outcome measure: ratio of current fat intake to the RDA (multiplied by 100) | |||||||||
| Andaleeb 2016 (‐) | Controlled before‐after study | NR | NR | 1134 HHs | NR | NR | NR | DID estimate –0.1, SE 0.00, P > 0.1 (7 years) | ▽ |
aEach triangle represents one study.
▲ = Favours the intervention, 95% CI excludes 0; △ = Unclear effect potentially favouring the intervention, 95% CI includes zero; ▼ = Favours the control, 95% CI excludes 0; ▽ = Unclear effect potentially favouring the control, 95% CI includes 0. (+): low overall risk of bias; (?): unclear overall risk of bias; (‐): high overall risk of bias.
CI: confidence interval; DID: difference in differences; HH: household; n: number; NR: not reported; RDA: recommended daily allowance; SD: standard deviation; SE: standard error.