Impact of price reductions, subsidies, or financial incentives on healthy food purchases and consumption: a systematic review and meta-analysis.

Poor diets are a global concern and are linked with various adverse health outcomes. Healthier foods such as fruit and vegetables are often more expensive than unhealthy options. This study aimed to assess the effect of price reductions for healthy food (including fruit and vegetables) on diet. We performed a systematic review and meta-analysis on studies that looked at the effects of financial incentives on healthy food. Main outcomes were change in purchase and consumption of foods following a targeted price reduction. We searched electronic databases (MEDLINE, EconLit, Embase, Cinahl, Cochrane Library, and Web of Science), citations, and used reference screening to identify relevant studies from Jan 1, 2013, to Dec 20, 2021, without language restrictions. We stratified results by population targeted (low-income populations vs general population), the food group that the reduction was applied to (fruit and vegetables, or other healthier foods), and study design. Percentage price reduction was standardised to assess the effect in meta-analyses. Study quality was assessed using the Cochrane Risk of Bias tool and Newcastle-Ottawa Scale. 34 studies were eligible; 15 took place in supermarkets and eight took place in workplace canteens in high-income countries, and 21 were targeted at socioeconomically disadvantaged communities. Pooled analyses of 14 studies showed a price reduction of 20% resulted in increases in fruit and vegetable purchases by 16·62% (95% CI 12·32 to 20·91). Few studies had maintained the price reduction for over 6 months. In conclusion, price reductions can lead to increases in purchases of fruit and vegetables, potentially sufficient to generate health benefits, if sustained.

Effectiveness and cost-effectiveness of the PLAN-A intervention, a peer led physical activity program for adolescent girls: results of a cluster randomised controlled trial.

BACKGROUND: Physical activity is associated with improved health. Girls are less active than boys. Pilot work showed that a peer-led physical activity intervention called PLAN-A was a promising method of increasing physical activity in secondary school age girls. This study examined the effectiveness and cost-effectiveness of the PLAN-A intervention. METHODS: We conducted a cluster randomised controlled trial with Year 9 (13-14 year old) girls recruited from 20 secondary schools. Schools were randomly assigned to the PLAN-A intervention or a non-intervention control group after baseline data collection. Girls nominated students to be peer leaders. The top 18 % of girls nominated by their peers in intervention schools received three days of training designed to prepare them to support physical activity. Data were collected at two time points, baseline (T0) and 5-6 months post-intervention (T1). Participants wore an accelerometer for seven days to assess the primary outcome of mean weekday minutes of moderate-to-vigorous physical activity (MVPA). Multivariable mixed effects linear regression was used to estimate differences in the primary outcome between the two arms on an Intention-to-Treat (ITT) basis. Resource use and quality of life were measured and a within trial economic evaluation from a public sector perspective was conducted. RESULTS: A total of 1558 girls were recruited to the study. At T0, girls in both arms engaged in an average of 51 min of MVPA per weekday. The adjusted mean difference in weekday MVPA at T1 was - 2.84 min per day (95 % CI = -5.94 to 0.25) indicating a slightly larger decline in weekday MVPA in the intervention group. Results were broadly consistent when repeated using a multiple imputation approach and for pre-specified secondary outcomes and sub-groups. The mean cost of the PLAN-A intervention was £2817 per school, equivalent to £31 per girl. Economic analyses indicated that PLAN-A did not lead to demonstrable cost-effectiveness in terms of cost per unit change in QALY. CONCLUSIONS: This study has shown that the PLAN-A intervention did not result in higher levels of weekday MVPA or associated secondary outcomes among Year 9 girls. The PLAN-A intervention should not be disseminated as a public health strategy. TRIAL REGISTRATION: ISRCTN14539759 -31 May, 2018.

Protocol for a cluster randomised controlled trial of a Peer-Led physical Activity iNtervention for Adolescent girls (PLAN-A).

BACKGROUND: Adolescent girls are less physically active than recommended for health, and levels decline further as they approach adulthood. Peers can influence adolescent girls' physical activity. Interventions capitalising on peer support could positively impact physical activity behaviour in this group. Building on promising feasibility work, the purpose of this cluster randomised controlled trial is to assess whether the Peer-Led physical Activity iNtervention for Adolescent girls (PLAN-A) increases adolescent girls' physical activity and is cost effective. METHODS: PLAN-A is a two-arm secondary school-based cluster randomised controlled trial, conducted with girls aged 13-14 years from twenty schools in the south west of England. The intervention requires participants to nominate influential girls within their year group to become peer supporters. The top 15% of girls nominated in each school receive three days of training designed to prepare them to support their peers to be more physically active during a ten-week intervention period. Data will be collected at two time points, at baseline (T0) and 5-6 months post-intervention (T1). Schools will be randomly allocated to the intervention (n = 10) or control (n = 10) arm after T0. At each time point, all consenting participants will wear an accelerometer for seven days to assess the primary outcome of mean weekday minutes of moderate-to-vigorous physical activity. Multivariable mixed effects linear regression will be used to estimate differences in the primary outcome between the two arms and will be examined on an Intention-to-Treat (ITT) basis. A self-report psychosocial questionnaire will be completed by participants to assess self-esteem and physical activity motivation. Resource use and quality of life will be measured for the purposes of an economic evaluation. A mixed-methods process evaluation will be conducted to explore intervention fidelity, acceptability and sustainability. Analysis of quantitative process evaluation data will be descriptive, and the framework method will be used to analyse qualitative data. DISCUSSION: This paper describes the protocol for the PLAN-A cluster randomised controlled trial, a novel approach to increasing adolescent girls' physical activity levels through peer support. TRIAL REGISTRATION: ISRCTN14539759-31 May, 2018.