Open Access Highly Accessed Study protocol

A cluster-randomized controlled trial to reduce sedentary behavior and promote physical activity and health of 8-9 year olds: The Transform-Us! Study

Jo Salmon1*, Lauren Arundell1, Clare Hume1, Helen Brown1, Kylie Hesketh1, David W Dunstan2, Robin M Daly1, Natalie Pearson3, Ester Cerin4, Marj Moodie5, Lauren Sheppard5, Kylie Ball1, Sarah Bagley1, Mai Chin A Paw6 and David Crawford1

Author Affiliations

1 Centre for Physical Activity and Nutrition Research, Faculty of Health, Medicine, Nursing and Behavioral Sciences, Deakin University, Victoria, Australia

2 Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia

3 School of Sport, Exercise and Health Sciences, Loughborough University, UK

4 Institute of Human Performance, The University of Hong Kong, Hong Kong, Hong Kong SAR

5 Deakin Health Economics, Faculty of Health, Medicine, Nursing and Behavioral Sciences, Deakin University, Victoria, Australia

6 Department of Public and Occupational Health, EMGO Institute for Health and Care Research, VU University Medical Center, Amsterdam, The Netherlands

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BMC Public Health 2011, 11:759  doi:10.1186/1471-2458-11-759

Published: 4 October 2011



Physical activity (PA) is associated with positive cardio-metabolic health and emerging evidence suggests sedentary behavior (SB) may be detrimental to children's health independent of PA. The primary aim of the Transform-Us! study is to determine whether an 18-month, behavioral and environmental intervention in the school and family settings results in higher levels of PA and lower rates of SB among 8-9 year old children compared with usual practice (post-intervention and 12-months follow-up). The secondary aims are to determine the independent and combined effects of PA and SB on children's cardio-metabolic health risk factors; identify the factors that mediate the success of the intervention; and determine whether the intervention is cost-effective.


A four-arm cluster-randomized controlled trial (RCT) with a 2 × 2 factorial design, with schools as the unit of randomization. Twenty schools will be allocated to one of four intervention groups, sedentary behavior (SB-I), physical activity (PA-I), combined SB and PA (SB+PA-I) or current practice control (C), which will be evaluated among approximately 600 children aged 8-9 years in school year 3 living in Melbourne, Australia. All children in year 3 at intervention schools in 2010 (8-9 years) will receive the intervention over an 18-month period with a maintenance 'booster' delivered in 2012 and children at all schools will be invited to participate in the evaluation assessments. To maximize the sample and to capture new students arriving at intervention and control schools, recruitment will be on-going up to the post-intervention time point. Primary outcomes are time spent sitting and in PA assessed via accelerometers and inclinometers and survey.


To our knowledge, Transform-Us! is the first RCT to examine the effectiveness of intervention strategies for reducing children's overall sedentary time, promoting PA and optimizing health outcomes. The integration of consistent strategies and messages to children from teachers and parents in both school and family settings is a critical component of this study, and if shown to be effective, may have a significant impact on educational policies as well as on pedagogical and parenting practices.

Trial registration

ACTRN12609000715279; Current Controlled Trials ISRCTN83725066