BMI values based on self-reported height and weight, if corrected for biases associated with socio-demographic characteristics of the survey respondents, can be used to provide accurate estimates of the proportion of overweight members of the population, but they still underestimate the proportion of obese population members. On the other hand, adjusted self-report measures do provide accurate estimates of health risks associated with variations in BMI, particularly when using parametric prediction models. Still, given the costs of data collection and the ability to reduce, even though not eliminate, systematic biases through adjustments using a few demographic variables, BMI values based on self-reported height and weight remain an important tool for population-based estimates of the health risks involved in obesity.
