College of Public Health and Human Sciences

Objective This study compares body mass index (BMI) classifications based on self-reported weights and heights with participants' perceptions of overweight and obesity status. Design, Setting and Participants Through semistructured interviews with Supplemental Nutrition Assistance Program clients (76% women, average age of 37 years, 41% white, 46% black) in 5 Maryland counties, this study assessed BMI calculations based on self-reported height and weight and self-perceptions of overweight and obese status (n = 239). Outcome Measures and Analysis Self-reported weights and heights were converted to BMI scores. The BMI categories were then compared with the participants' answer about whether they considered themselves to be overweight or obese. Participants who correctly and incorrectly classified themselves were counted. Results Preliminary results show that 54% of the respondents said they were neither overweight nor obese; however, using calculated BMI, 93% were in one of those categories. Ten percent classified themselves as obese, whereas BMI scores showed that 60% were in that category. Additionally, 36% said they considered themselves overweight, but BMI scores indicated that 33% were (3% were actually obese). Further data analysis will evaluate self-rating and how that related to demographics. Conclusions and Implications Research already demonstrates that calculations based on self-reported height and weight result in misclassification of approximately 20% of individuals. This study shows that self-identification of overweight or obese status is even less accurate, with participants underestimating their BMI classifications. Thus, individuals may not identify a need to lose weight, creating a barrier to making positive diet and exercise changes. Funding for SNAP-Ed is provided by the USDA in cooperation with the Maryland Department of Human Resources and University of Maryland.