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

Abstract

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.

A systematic review of economic evaluations of interventions targeting childhood overweight and obesity

“…The remaining four studies stated that they did not find evidence of cost-effectiveness. 84,90,92,98 Cost-effectiveness also varied by ethnicity, age, and socioeconomic status (SES). One study estimated lower ICERs for a multicomponent through-school physical activity and nutrition program in the M aori subpopulation and children in middle SES schools compared to the entire population and lower ICERs for older children across all subgroups compared with younger children.…”

“…31, One school or student was usually derived from study records, which included data such as intervention materials, cost of the venue for physical activities, teacher and trainer or facilitator time, travel and administration costs, and miscellaneous expenses. 97,98 The control arms were generally assigned no costs or negligible up-front costs. A prevalent costing assumption was that interventions operated in a steady state, not requiring one-off start-up costs.…”

A systematic review and meta-analysis of the benefits of school-based, peer-led interventions for leaders

“…Of the six studies investigating physical activity as an outcome of interest, only one reported an increase in leaders' physical activity 37 , though this was measured via self-report. Where leaders' physical activity was assessed objectively (using pedometers or accelerometers), these interventions did not increase leaders' physical activity 10,45 . Several studies examined the effect of their intervention on leaders' self-reported diet and sedentary behaviours, though there was no evidence that school-based peer-led interventions reduce the sedentary behaviours of the leaders involved 53,54 .…”

“…Due to a lack of sufficient data, the corresponding meta-analyses were not conducted for behavioural and physical outcomes. The following potential categorical moderators of effects were identified after PROSPERO registration: (i) age (child [5][6][7][8][9][10][11][12] vs. adolescent [13][14][15][16][17][18]), (ii) study design (experimental vs. quasi-experimental), (iii) study duration (≤ 10 weeks vs. > 10 weeks) and (iv) congruence of age between leaders and peer recipients (same age vs. cross-age). Due to the homogeneity of moderators across the studies included in the meta-analyses (e.g., all studies in the meta-analyses had child leaders), we were not able to conduct moderator analyses.…”

“…Whilst five studies reported at least one peer-led session per week, other studies did not focus on implementing formal sessions, instead encouraging leaders to promote certain behaviours through conversations with friends or by modelling these behaviours 9,10 . The remaining studies either did not report the number of peer-led sessions per week or had less than one session per week.…”