García-Hermoso A, Marina R Relationship of weight status, physical activity and screen time with academic achievement in adolescents. Obes Res Clin Pract. 2017 Jan - Feb;11(1):44-50. doi: 10.1016/j.orcp.2015.07.006. Epub 2015 Aug 3.
Griffiths LJ, Parsons TJ, Hill AJ Self-esteem and quality of life in obese children and adolescents: a systematic review. Int J Pediatr Obes. 2010 Aug;5(4):282-304. doi: 10.3109/17477160903473697. Review.
Lera L, Fretes G, González CG, Salinas J, Vio del Rio F [Validity of an instrument for assessing food consumption, food habits and cooking skills in 8-11 years old students]. Nutr Hosp. 2015 May 1;31(5):1977-88. doi: 10.3305/nh.2015.31.5.8607. Spanish.
Mei H, Xiong Y, Xie S, Guo S, Li Y, Guo B, Zhang J The impact of long-term school-based physical activity interventions on body mass index of primary school children - a meta-analysis of randomized controlled trials. BMC Public Health. 2016 Mar 1;16:205. doi: 10.1186/s12889-016-2829-z. Review.
Oosterhoff M, Joore M, Ferreira I The effects of school-based lifestyle interventions on body mass index and blood pressure: a multivariate multilevel meta-analysis of randomized controlled trials. Obes Rev. 2016 Nov;17(11):1131-1153. doi: 10.1111/obr.12446. Epub 2016 Jul 19. Review.
Sobol-Goldberg S, Rabinowitz J, Gross R School-based obesity prevention programs: a meta-analysis of randomized controlled trials. Obesity (Silver Spring). 2013 Dec;21(12):2422-8. doi: 10.1002/oby.20515. Epub 2013 Aug 13. Review.
Wang YC, McPherson K, Marsh T, Gortmaker SL, Brown M Health and economic burden of the projected obesity trends in the USA and the UK. Lancet. 2011 Aug 27;378(9793):815-25. doi: 10.1016/S0140-6736(11)60814-3. Erratum in: Lancet. 2011 Nov 19;378(9805):1778.
Withrow D, Alter DA The economic burden of obesity worldwide: a systematic review of the direct costs of obesity. Obes Rev. 2011 Feb;12(2):131-41. doi: 10.1111/j.1467-789X.2009.00712.x. Review.
Interventional studies are often prospective and are specifically tailored to evaluate direct impacts of treatment or preventive measures on disease.
Observational studies are often retrospective and are used to assess potential causation in exposure-outcome relationships and therefore influence preventive methods.
Expanded access is a means by which manufacturers make investigational new drugs available, under certain circumstances, to treat a patient(s) with a serious disease or condition who cannot participate in a controlled clinical trial.
Clinical trials are conducted in a series of steps, called phases - each phase is designed to answer a separate research question.
Phase 1: Researchers test a new drug or treatment in a small group of people for the first time to evaluate its safety, determine a safe dosage range, and identify side effects.
Phase 2: The drug or treatment is given to a larger group of people to see if it is effective and to further evaluate its safety.
Phase 3: The drug or treatment is given to large groups of people to confirm its effectiveness, monitor side effects, compare it to commonly used treatments, and collect information that will allow the drug or treatment to be used safely.
Phase 4: Studies are done after the drug or treatment has been marketed to gather information on the drug's effect in various populations and any side effects associated with long-term use.