Table 2 displays arithmetic means for self-reported (SR) and measured (M) heights, weights and BMIs, as well as the discrepancies (DIS) between the self-reported and measured variables. In addition to information about the standard errors, standardized effect sizes for the discrepancy scores are added. As the rightmost column shows, the overall population mean for self-reported heights represents a modest overestimate of one centimeter, while self-reported weight represents an underestimate of measured weight by 3/4 of a kilogram (1.6 pounds). The net result is that the mean population estimate of the BMI, based on the self-reported heights and weights, is lower than the mean estimate of the measured BMI by 0.59 units. The effect sizes of the height and weight discrepancies for the total population suggest that height overestimates contribute more to the total population BMI discrepancies than weight underestimates. However, 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
