The health status of obese individuals in Canada

To determine whether there is a clinically relevant difference in the health state utilities of obese and non-obese individuals as measured by the Health Utility Index Mark III. Secondary analysis of the population-based, cross-sectional, interviewer-administered National Population Health Survey (NPHS), 1996-1997. A probability sample of house-dwelling Canadians, excluding populations on First Nations Reserves, Canadian Armed Forces Bases, the Yukon and Northwest Territories, and long-term residents of hospitals or residential care facilities. The sub-sample used in this analysis consisted of 38 151 respondents (52.4% male) between the ages of 20 and 64 y, excluding pregnant women. Health Utilities Index-Mark III (HUI3) scores were used to define normal weight (body mass index (BMI) 19-24.9 kg/m(2)), overweight (BMI 25-29.9 kg/m(2)), obese (BMI 30-34.9 kg/m(2)), and morbidly obese (BMI> or =35 kg/m(2)) individuals. HUI3 scores were age- and gender-standardized. The overall prevalence of obesity (BMI> or =30 kg/m(2)) in this Canadian population was 13.3%. The average difference in HUI3 scores between normal weight and morbidly obese respondents was 0.04 (P