Enhancing physical activity in early childhood for 3–5-year-old children born very preterm: protocol for an Australian randomised controlled trial of Active-Prem

Introduction Children born very preterm (VPT: <32 weeks’ gestation) are less physically active than their term-born peers and face greater barriers to physical activity (PA). PA has many benefits and is important for children born VPT who are at increased risk for poor physical and mental health. This paper describes the protocol for a randomised controlled trial (RCT) evaluating the effectiveness of Active-Prem (a six-step intervention combining parent support, coach training and a term of community-based PA) compared with Goal Setting, at improving PA for children born VPT living in Australia. Methods and analysis Type 1 hybrid effectiveness-implementation RCT involving 204 children born VPT (3–5 years’ corrected age) and their parent/caregiver. Active-Prem comprises: (1) setting PA participation goals; (2) online support for parents through the co-designed Active Start Active Prems programme; (3) matching children with an activity and a PA coach in their local community; (4) upskilling coaches through the co-designed Coaching Essentials: Premature Children in Sport programme; (5) an introduction session for children and families to their chosen activity and (6) one term (8–11 weeks) of the chosen activity, facilitated by a coach who has completed Coaching Essentials. Participants allocated to Goal Setting will complete step 1 only. The primary outcome is PA measured using 7-day accelerometry at postintervention. Secondary effectiveness outcomes include parent-reported PA and goal attainment. Implementability outcomes include acceptability, feasibility, fidelity and cost-effectiveness. For effectiveness outcomes, mean differences or risk differences between groups will be estimated using linear regression for continuous outcomes or binomial regression for binary outcomes. Implementability outcomes will be summarised using descriptive statistics (quantitative measures) or thematic analysis (qualitative measures). Ethics and dissemination This study has approval from the University of Melbourne Human Research Ethics Committee (2025-31093-64376-3). Findings will be disseminated through peer-reviewed publications, conference presentations, digital and print media and to participants. Trial registration number ACTRN12625000183482.