Anthropometric outcomes of a motivational interviewing school-based randomized trial involving adolescents with overweight
Motivational interviewing (MI) is an effective method to promote weight loss that can be delivered by non-mental health providers. The aim of this study was to evaluate whether MI was superior to conventional counseling to improve the anthropometric outcomes of adolescents with obesity/overweight. It was a controlled cluster randomized trial with parallel design in a school setting. The study included two groups: Motivational Interviewing Group (MIG) and control group (Conventional Intervention Group, CIG). Students participated in three face-to-face 30-min interviews, 3 months apart. Outcomes were BMI z-score, abdominal circumference, percentages of fat mass and muscle mass, and blood pressure. Sessions were coded with the Motivational Interviewing Treatment Integrity (MITI) manual. Mixed repeated-measures ANOVAs were used to assess the group versus time interaction. Effect sizes were calculated for each ANOVA with eta-squared measures (η2). Eighty-three adolescents finished the protocol. While MIG participants showed a significant improvement in all anthropometric scores at 6 months, CIG participants showed an unfavorable change in those variables.
Conclusion: Our results provide additional evidence of the short-term usefulness of a school-based MI intervention on anthropometric outcomes of adolescents with obesity/overweight, demonstrating that pediatricians can play an important role in the prevention and management of pediatric obesity.
What is Known:
• Although MI has been recognized as an effective counseling style for behavioral change in weight loss, there are few reports about the anthropometric outcomes of interventions with adolescents being treated for obesity/overweight.
• Our study showed significant positive changes in anthropometric variables (BMI z-score, abdominal circumference, percentage of fat mass, percentage of muscular mass, systolic and diastolic blood pressure) after only three face-to-face sessions over 6 months.
What is New:
• MI delivered by non-mental health providers in a school setting seems to have short-term usefulness in a program aiming the treatment of obese/overweight adolescents.
KeywordsPediatric obesity School health services Motivational interviewing Body mass index Body composition Blood pressure
Body mass index
Conventional Intervention Group
Motivational Interviewing Group
Motivational Interviewing Treatment Integrity
World Health Organization
The authors thank the teachers of the schools involved in the study (Alfredo dos Reis Silveira High School, José Afonso High School, Manuel Cargaleiro High School, Amora High School, Terras de Larus Basic 2/3 School, Fernão Mendes Pinto High School, Emídio Navarro High School, Professor Ruy Luís Gomes High School), the Seixal and Almada Municipalities, the associations Independente Futebol Clube Torrense and Sociedade Recreativa União Pragalense, and the Holon Pharmacy Group®.
The study was not funded by any grant but the Portuguese Municipalities of Seixal and Almada, where the study took place, partially funded the physical activities for the participants. Dieticians from Holon Pharmacy Group® gave free dietetic counseling, which did not involve any selling of dietetic products in the pharmacies. Neither the municipalities nor the above mentioned pharmacy group had any role in the study protocol or in any decisions related to the study.
Silvia Freira: (1) conception and design of the study, acquisition of data, and analysis and interpretation of data, (2) drafting the article, and (3) final approval of the version to be submitted
Marina Serra Lemos: (1) conception and design of the study and analysis and interpretation of data, (2) revising the article critically for important intellectual content, and (3) final approval of the version to be submitted
Helena Fonseca: (1) analysis and interpretation of data, (2) revising the article critically for important intellectual content, and (3) final approval of the version to be submitted
Geoffrey Williams: (1) analysis and interpretation of data, (2) revising the article critically for important intellectual content, and (3) final approval of the version to be submitted
Marta Ribeiro: (1) conception and design of the study and acquisition of data, (2) revising the article critically for important intellectual content, and (3) final approval of the version to be submitted
Fernanda Pena: (1) conception and design of the study and acquisition of data, (2) revising the article critically for important intellectual content, and (3) final approval of the version to be submitted
Maria do Céu Machado: (1) conception and design of the study and analysis and interpretation of data, (2) revising the article critically for important intellectual content, and (3) final approval of the version to be submitted
This study was not funded by any grant, but the municipalities where the study took place (Seixal and Almada, Portugal) partially funded the physical activities for the participants. Additionally, pharmacies from Group Holon® gave free dietetic counseling, without selling any dietetic products. Neither the municipalities nor the pharmacies had any influence on the study protocol or on the analysis of results. Authors do not have any financial relationship with the organizations that sponsored the research.
This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
The Study is called IMAGINE and is registered at Clinicaltrials.gov database with the number NCT02745795.
Approval to conduct the study was granted by the local research ethics committees (equivalent to a Human Subjects Review Boards). The study is called IMAGINE and is registered in Clinicaltrials.gov with the number NCT02745795. The full trial protocol can be accessed at the repositorium of the University which supervised the study (University of Lisbon). The students who agreed to participate provided written assent and their parents/guardians were asked to sign an informed consent, which was obtained from all individual participants included in the study. All procedures performed in this study involving human participants were in accordance with the institutional and/or national research committee and with the Code of Ethics of the World Medical Association (1964 Helsinki Declaration) and its later amendments or comparable ethical standards for experiments involving humans and with uniform requirements for manuscripts Submitted to Biomedical Journals.
Informed consent was obtained from all individual participants included in the study.
- 1.Ball GD, Mackenzie-Rife KA, Newton MS, Alloway CA, Slack JM, Plotnikoff RC, Goran MI (2011) One-on-one lifestyle coaching for managing adolescent obesity: findings from a pilot, randomized controlled trial in a real-world, clinical setting. Paediatr Child Health 16:345–350CrossRefPubMedPubMedCentralGoogle Scholar
- 17.Graffar M (1956) Une méthode de classification sociale d'échantillons de population. Courrier VI:455–459Google Scholar
- 22.Lurbe F, Agabiti-Rosei E, Cruickshank JK, Dominiczak A, Erdine S, Hirth A, Invitti C, Litwin M, Mancia G, Pall D, Rascher W, Redon J, Schaefer F, Seeman T, Sinha M, Stabouli S, Webb NJ, Wühl E, Zanchetti A (2016) 2016 - European Society of Hypertension (ESH) guidelines for the management of high blood pressure in children and adolescents. J Hypertens 85:167–169Google Scholar
- 24.Miller WR, Rollnick S (2013) Motivational interviewing: helping people change, third ed. Guilford Press, New YorkGoogle Scholar
- 27.Naar-King S, Suarez M (2011) Motivational interviewing with adolescents and young adults, first ed. Ther Guilford Press, New YorkGoogle Scholar
- 28.Naar-King S, Ellis DA, Carcone AI, Templin T, Jacques-Tiura AJ, Hartlieb KB, Cunningham P, Jen KKC (2016) Sequential multiple assignment randomized trial (SMART) to construct weight loss interventions for African American adolescents. J Clin Child Adolesc Psychol 45:428–441CrossRefPubMedGoogle Scholar
- 30.Pate RR, Davis MG, Robinson TN, Stone EJ, McKenzie TL, Young JC (2006) Promoting physical activity in children and youth: a leadership role for schools: a scientific statement from the American Heart Association Council on Nutrition, Physical Activity, and Metabolism (Physical Activity Committee) in collaboration with the Councils on Cardiovascular Disease in the Young and Cardiovascular Nursing. Circulation 114:1214–1224CrossRefPubMedGoogle Scholar
- 33.Riiser K, Løndal K, Ommundsen Y, Småstuen MC, Misvær N, Helseth S (2014) The outcomes of a 12-week internet intervention aimed at improving fitness and health-related quality of life in overweight adolescents: the young & active controlled trial. PLoS One 9:e114732CrossRefPubMedPubMedCentralGoogle Scholar
- 39.Videira-Silva A, Fonseca H (2017) The effect of a physical activity consultation on body mass index z-score of overweight adolescents: results from a pediatric outpatient obesity clinic. 1–6Google Scholar
- 40.Viggiano E, Viggiano A, Costanzo A, Viggiano A, Viggiano A, Andreozzi E, Romano V, Vicidomini C, Di Tuoro D, Gargano G, Incarnato L, Fevola C, Volta P, Tolomeo C, Scianni G, Santangelo C, Apicella M, Battista R, Raia M, Valentino I, Palumbo M, Messina G, Messina A, Monda M, De Luca M, De Luca B, Amaro S (2018) Healthy lifestyle promotion in primary schools through the board game Kaledo: a pilot cluster randomized trial. Eur J Pediatr 69:1–5Google Scholar