The ERS Eating and Health Module, a supplement to the American Time Use Survey (ATUS), included questions on height and weight so that respondents' Body Mass Index (BMI-a measure of body fat based on height and weight) could be calculated and analyzed with ATUS time-use data in obesity research. Some respondents did not report height and/or weight, and BMIs could not be calculated for them. Analyses focusing on correlations between BMIs and time use could be biased if respondents who did not report height and/or weight differ significantly in other observable characteristics from the rest of the survey respondents. However, findings reveal that any nonresponse bias associated with the height and weight data appears to be small and would not affect future analyses of BMIs and time-use pattern correlations.