Open Access Highly Accessed Study protocol

The sydney playground project: popping the bubblewrap - unleashing the power of play: a cluster randomized controlled trial of a primary school playground-based intervention aiming to increase children's physical activity and social skills

Anita C Bundy1*, Geraldine Naughton2, Paul Tranter3, Shirley Wyver4, Louise Baur5, Wendy Schiller6, Adrian Bauman7, Lina Engelen1, Jo Ragen1, Tim Luckett1, Anita Niehues1, Gabrielle Stewart1, Glenda Jessup1 and Jennie Brentnall1

Author Affiliations

1 Faculty of Health Sciences, University of Sydney, Lidcombe, Australia

2 Centre of Physical Activity across the Lifespan, Australian Catholic University, Melbourne, Australia

3 School of Physical, Environmental and Mathematical Sciences, University of New South Wales, Canberra, Australia

4 Institute of early childhood, Macquarie University, Sydney, Australia

5 Paediatrics & Child Health, University of Sydney, Westmead, Australia

6 School of Education, University of South Australia, Adelaide, Australia

7 Public Health, University of Sydney, Sydney, Australia

For all author emails, please log on.

BMC Public Health 2011, 11:680  doi:10.1186/1471-2458-11-680

Published: 1 September 2011



In the Westernised world, numerous children are overweight and have problems with bullying and mental health. One of the underlying causes for all three is postulated to be a decrease in outdoor free play. The aim of the Sydney Playground Project is to demonstrate the effectiveness of two simple interventions aimed to increase children's physical activity and social skills.


This study protocol describes the design of a 3-year cluster randomised controlled trial (CRCT), in which schools are the clusters. The study consists of a 13-week intervention and 1 week each of pre-and post-testing. We are recruiting 12 schools (6 control; 6 intervention), with 18 randomly chosen participants aged 5 to 7 years in each school. The two intervention strategies are: (1) Child-based intervention: Unstructured materials with no obvious play value introduced to the playground; and (2) Adult-based intervention: Risk reframing sessions held with parents and teachers with the aim of exploring the benefits of allowing children to engage in activities with uncertain outcomes. The primary outcome of the study, physical activity as measured by accelerometer counts, is assessed at baseline and post-intervention. Additional assessments include social skills and interactions, self-concept, after school time use and anthropometric data. Qualitative data (i.e., transcriptions of audio recordings from the risk reframing sessions and of interviews with selected teacher and parent volunteers) are analysed to understand their perceptions of risk in play. The control schools have recess as usual. In addition to outcome evaluation, regular process evaluation sessions are held to monitor fidelity to the treatment.


These simple interventions, which could be adopted in every primary school, have the potential of initiating a self-sustaining cycle of prevention for childhood obesity, bullying and mental ill health.

Trial registration

Australian and New Zealand Clinical Trials Registration Number ACTRN12611000089932.