the discrepancies in each BMI class hint at linear trends such that overestimates of self-reported height become larger with larger measured BMI categories. The weight discrepancies indicate overestimates of self-reported weight in lower BMI categories and underestimates of self-reported weight in the higher BMI categories. The net result is a linear trend towards declining self-reported BMI values relative to measured BMI values. A linear regression model predicting the discrepancy between self-reported and measured BMI values (BMIDIS) based on the measured BMI (BMIM) values leads to the following estimates: BMIDIS = 2.283 - 0.102 BMIM, with standard errors of 0.134 for the intercept and 0.005 for the regression coefficients. Using this equation, self-reported BMI values would be unbiased estimates (i.e., BMIDIS = 0) of actual (measured) BMI for persons with a BMI of 22.4 (2.283/0.102), but would overstate actual BMI at lower BMI values and understate it at higher BMI values. Furthermore, the effect sizes for the height and weight discrepancies in the underweight category suggest that weight overestimates play a large role in the BMI overestimates in this group. By comparison, the effect sizes among the obese indicate that both height overestimates and weight underestimates contribute in equal measure to
