Effects of the informed health choices secondary school intervention after 1 year: a prospective meta-analysis using...

Critical thinking about health choices is essential to avoid being misled by unreliable information and to use reliable information appropriately. The aim of this prospective meta-analysis was to synthesize the results of 1-year follow-up data from three cluster-randomized trials of an intervention designed to teach lower secondary school students to think critically about health choices. Only one other randomized trial has evaluated a school-based intervention to teach adolescents to think critically about health choices. That trial compared two teaching strategies to teach statistical reasoning. It did not assess long-term learning-retention.

We conducted the trials in Kenya, Rwanda, and Uganda. The intervention included providing a 2-3-day teacher training workshop and digital resources for ten lessons. The intervention focused on nine key concepts. We did not intervene in control schools. The primary outcome was a passing score on a test (≥ 9 of 18 multiple-choice questions answered correctly). We performed random effects meta-analyses to estimate the overall intervention effects. We calculated learning retention as the test results in the intervention schools after 1 year relative to just after the intervention, adjusted for chance.

Altogether, 244 schools (11,344 students) took part in the three trials. Follow-up data was collected for 8298 students (73%). The overall odds ratio for the primary outcome after 1 year was 3.6 (95% CI: 1.9-7.1; p = 0.0001) in favor of the intervention, whereas it was 5.5 (95% CI: 3.0-10.2) just after the intervention. This corresponds to 25.6% (95% CI: 21.1-30.0%) more students in the intervention schools passing the test after 1 year versus 33.3% (95% CI: 28.7-37.8%) just after the intervention. Overall, 2273 (52.6%) of 4324 students in intervention schools had a passing score after 1 year compared to 3397 (58.1%) of 5846 students just after the intervention, indicating 88.3% learning retention.

One year after the intervention, we still found a positive effect on the ability of students to think critically about health choices, but 5.5% fewer students in the intervention schools had a passing score. The certainty of the evidence was also lower due to 27% of students being lost to follow-up.

The protocol for this prospective meta-analysis was registered with PROSPERO May 31, 2022, ID 336580. The three randomized trials were registered in the Pan African Clinical Trial Registry February 15, 2022, PACTR202203880375077; April 5, 2022, PACTR20220488391731; and April 14, 2022, PACTR202204861458660.