Accuracy of self-reported weight compared to measured BMI among rural middle school students in Michigan

Aim Measured body mass index (BMI) is recommended for field-based assessments of overweight and obesity in all population groups. However, self-reported perception of body weight is frequently used in surveys targeting overweight and obese individuals. This study’s purpose was to examine the accuracy of self-reported weight compared to measured BMI among rural middle school students in Michigan. Subject and methods A sample of 1995 students aged 11 and 12 were recruited over 5 years from six rural school districts in mid-Michigan. Data were collected using an interviewer-administered questionnaire with questions from the Youth Risk Behavior Survey. Height and weight were measured by research assistants and BMI calculated. Results Although only 3.5% of the students considered themselves very overweight, 26.4% were in the obese category of BMI. Almost a quarter (23.7%) reported they were slightly overweight, but these were all obese by BMI standards. Conversely, while 18.5% reported they were underweight, only 0.9% were truly underweight by BMI standards. A statistically significant difference ( P