Do dietary and physical activity interventions in 1 adolescents provide a cost-effective use of healthcare 2 resources? Model development and illustration based on 3 the Engaging Adolescents in Changing Behaviour (EACH- 4 B) programme 5 6 Authors: Neelam Kalita 1 , Keith Cooper 1 , Janis Baird 2;3 , Kathryn Woods-Townsend 3;4 , Keith 7 M Godfrey 2;3 , Cyrus Cooper 2;6;7 , Hazel Inskip 2;3 , Mary Barker 2;3;5 , Joanne Lord 1 and the 8 EACH-B study group 9 10 Affiliations: 11 1 Southampton Health Technology Assessments Centre, University of Southampton, UK 12 2 MRC Lifecourse Epidemiology Unit, University of Southampton, Southampton, UK 13 3 NIHR Southampton Biomedical Research Centre, University of Southampton and University 14 Hospital Southampton NHS Foundation Trust, Southampton, UK 15 4 Southampton Education School, Faculty of Social Sciences, University of Southampton, 16 Southampton, UK 17 5 School of Health Sciences, University of Southampton, Southampton, UK 18 6 Faculty of Medicine, University of Southampton 19 7 Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of 20 Oxford 21 22 23 Corresponding author: Neelam Kalita 24 Email: N.Kalita@soton.ac.uk 25 26 27 28 All rights reserved. No reuse allowed without permission. (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. The copyright holder for this preprint this version posted May 8, 2021. ; https://doi.org/10.1101/2021.05.05.21256672 doi: medRxiv preprint NOTE: This preprint reports new research that has not been certified by peer review and should not be used to guide clinical practice.