Considerations and lessons learned from designing a motivational interviewing obesity intervention for young people attending dental practices: A study protocol paper ☆ Marie Murphy a , Jessie Porter a, ⁎, Huda Yusuf a , Antiopi Ntouva a , Tim Newton b , Anna Kolliakou c , Helen Crawley d , Georgios Tsakos a , Hynek Pikhart a , Richard G. Watt a a UCL Research Department of Epidemiology and Public Health, University College London, 1–19 Torrington Place, London WC1E 6BT, UK b Division of Health and Social Care Research, King's College London, Dental Institute, Caldecot Road London SE5 9RW, UK c Department of Psychosis Studies, Institute of Psychiatry, King's College London, De Crespigny Park, SE5 8AF, UK d First Steps Nutrition Trust, 112 Queens Road, London SW19 8LS, UK article info abstract Article history: Received 5 April 2013 Received in revised form 20 June 2013 Accepted 22 June 2013 Available online 28 June 2013 Background: With the prevalence of child obesity increasing worldwide, and the consumption of sugar-sweetened beverages identified as a major contributor to obesity in adolescents, there is a need for effective interventions aimed at dietary behaviour change in this group. Primary dental care settings are in an ideal position to influence adolescents' dietary behaviours, yet have been under-utilised for this purpose. Motivational Interviewing (MI) has shown promise in influencing other health behaviours. However, there is lack of published methodologies on which to base the design of such interventions, and limited evidence on its effectiveness in influencing dietary change. We undertook a study to test the feasibility of a MI intervention aimed at reducing soft drink consumption in adolescents attending dental surgeries. We present the study design for the development and evaluation of the intervention. Method: Ten dental practices in north London were randomised into control or intervention. Adolescent participants in control settings received routine advice and intervention participants received a brief MI intervention. The intervention was designed using comprehensive stakeholder engagement and consisted of 3–4 short MI sessions and a maintenance phase delivered by trained researchers through the use of age-specific resources. Process evaluation was carried out using qualitative and quantitative methods to assess intervention feasibility in a primary dental care setting. Discussion: By focussing on the development and evaluation of the intervention, this paper contributes to the limited available knowledge and identifies methodological considerations for undertaking a MI intervention for dietary change in adolescents in primary dental care settings. © 2013 Elsevier Inc. All rights reserved. Keywords: Obesity Adolescents Motivational interviewing Soft drinks Primary dental care Protocol 1. Background Childhood obesity is increasing worldwide, with rates doubling over the past three decades, including in the UK [1]. Evidence has shown that obesity which tracks from childhood to adulthood, is a leading cause of preventable deaths and a major risk factor for cardiovascular disease, type 2 diabetes and cancers [2]. Obesity also has a significant impact on self- esteem and quality of life [3]. The increase in obesity has resulted in escalating healthcare costs and is a significant burden on healthcare systems globally [4]. A substantial body of evidence suggests that a major con- tributing factor to the obesity epidemic, especially amongst children, is the consumption of sugar-sweetened beverages (SSBs) [5–8]. A recent meta-analysis showed that children with the highest intakes of SSBs have an increased risk of being Contemporary Clinical Trials 36 (2013) 126–134 ☆ Trial Registration: ISRCTN 04152711. ⁎ Corresponding author. Tel.: +44 207 679 1253. E-mail address: jessie.porter@ucl.ac.uk (J. Porter). 1551-7144/$ – see front matter © 2013 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.cct.2013.06.016 Contents lists available at SciVerse ScienceDirect Contemporary Clinical Trials journal homepage: www.elsevier.com/locate/conclintrial