Background: Height and weight information is commonly used in clinical trials and in making therapeutic decisions in medical practice. In both settings, the data are often obtained by self-report. If erroneous, this practice could lead to inaccuracies in estimating renal function and medication doses or to inaccurate outcomes of research studies. Previous publications have reported lack of reliability of self-reported weight and height in the general population but have not addressed age-specific and ethnicity-specific subgroups in the U.S. population. The inaccuracy of self-reported weight and height could be particularly significant in times of considerable changes in body weight, such as at menopause, which is often associated with weight gain. Methods: We assessed the validity of self-reported height and weight in 428 women within the first 5 years of menopause, 70.6% of whom were Hispanic. Results: Participants overestimated their height by 2.2 -3.5 cm (mean -standard deviation [SD]) and underestimated their weight by 1.5 -2.9 kg. As a group, based on self-reported measures, 33.3% were misclassified with respect to body mass index (BMI) category, and the difference between measured BMI and self-reported BMI was similar between Hispanic white and non-Hispanic white women, positively related to measured weight, and inversely related to measured height, years from menopause, and multiple parity. Conclusions: From the public health perspective, inaccurate self-report could lead to a considerable underestimation of the current obesity prevalence rates. In our study population, the prevalence of obesity (BMI ‡ 30 kg/m