Questionnaires and surveys are commonly used for data collection in epidemiological studies, but non-response or poor representativeness reduces the effective sample size and introduces bias.
The goal of this methodological review is to identify effective methods, strategies, and incentives to increase response to questionnaires and surveys among adolescents.
An iterative search strategy to May 2022 developed by an information specialist will be employed. We will assess the eligibility of each trial using pre-defined criteria. We will include randomized controlled trials (RCTs) or quasi randomized in first instance and non-randomized (controlled studies) in the event there are not enough RCTs or quasi RCTs.
To maximize efficiency, we will use machine learning functions in the systematic review software EPPI-reviewer. We will extract data on trial participants, the intervention, the number of randomized to intervention and comparison groups. If data is available, for each strategy we will estimate pool odds ratios and 95% confidence intervals in a random-effect model. We will assess evidence for selection bias if the number of trials allow us. The heterogeneity among trials will be explored using Chi2 test and the degree of incosistency between trial results with I2. If statistical pooling is not feasible, we will use the Synthesis Without Meta analysis (SWiM) guideline checklist to report the results narratively.
