Academic journal article Canadian Journal of Public Health

Ten-Year Trends in Overweight/obesity among Ontario Middle and High School Students and Their Use in Establishing Baseline Measures for Government Reduction Targets

Academic journal article Canadian Journal of Public Health

Ten-Year Trends in Overweight/obesity among Ontario Middle and High School Students and Their Use in Establishing Baseline Measures for Government Reduction Targets

Article excerpt

Widespread concern in the public health community about increasing levels of overweight and obesity among children and youth has resulted in the development of a number of policy and program initiatives designed to address this problem in Canada and elsewhere.1-4 For example, in 2012, the Ontario government established the ambitious target of reducing childhood obesity by 20% within five years.5 Subsequently, the Ministry of Health and Long-Term Care (MOHLTC) established the Healthy Kids Panel, which outlined a strategy for achieving this target by the year 2018 through a number of approaches aimed to benefit children and youth.6 More recently the Ministry announced funding to 45 communities in Ontario for the Healthy Kids Community Challenge, designed to address the issue of childhood obesity through community-based interventions to promote physical activity, healthy eating and adequate sleep.7 Given the health concerns regarding child obesity and governmental responses to address this issue, it is important to ensure that overweight and obesity levels among children and youth are tracked over time, and that policy and program interventions, including natural experiments,8 are assessed in relation to stability and change in prevalence.8-10

Shield's earlier (2006) study on trends in Canada, using the International Obesity Task Force (IOTF) criteria, describes large and significant increases in the prevalence of overweight and obesity (based on direct measures of height and weight in calculating body mass index [BMI]) among youth (aged 12-17) between 1978-79 (14% combined overweight and obesity) and 2004 (29% combined).11 A more recent assessment of obesity among Canadian youth (aged 12-17), based on the 2009 and 2011 waves of the Canadian Health Measures Survey, indicates the prevalence of combined overweight and obesity to be 26.9% (IOTF cut-points) or 30.1% (World Health Organization [WHO] cut-points) with higher levels among males.12

There have been no representative Ontario-level reports of trends in overweight/obesity for specific age by sex subgroups of children and youth based on either directly measured or self-reported height and weight. For example, while provincial estimates based on self-reported data from the Canadian Community Health Survey are analyzed in broad age groups (e.g., 12-17), the sample size is not sufficient to provide stable estimates within age and sex subgroups. In this paper we have two objectives. First, we examine 10-year (2003-2013) trends in the prevalence of overweight or obesity derived from selfreported height and weight among Ontario youth, based on data from the Ontario Student Drug Use and Health Survey (OSDUHS) and using the IOTF criteria cut-points. This trend analysis provides the context for our second objective. We establish data from the 2013 cycle of the survey to serve as baseline for subsequent tracking of progress in attaining the MOHLTC's 20% reduction target and for the assessment of provincial-level interventions designed to reach that target.


Study design

Our trend analyses were conducted using a stacked dataset accumulating six cycles for the period covering surveys in years 2003, 2005, 2007, 2009, 2011 and 2013. Self-reported height and weight data were collected during each of these survey years. The multi-year microdata contain information on 38,407 students enrolled in 778 schools (stage 1 primary sample unit clusters) distributed among 78 region-by-school level-by-year strata. See Kish13 and Korn and Graubard14 for more detail on combining multiple complex surveys. Each cycle was based on a target sample of 7th-12th graders enrolled in provincially funded English and French language schools in the public and Catholic school sectors in Ontario. Students excluded as being outof-scope were those in private schools; those schooled in correctional or health facilities; students schooled on First Nations reserves, military bases and in remote areas of Northern Ontario; and the few who were home-schooled. …

Search by... Author
Show... All Results Primary Sources Peer-reviewed


An unknown error has occurred. Please click the button below to reload the page. If the problem persists, please try again in a little while.