The large, population based samples, and analysis of repeated-cross sections of the population constitutes considerable strengths. The repeated cross-section approach is particularly well-suited for estimating overall change within a population.58 The use of self-reported height and weight to determine BMI are limitations, and could potentially bias the estimates of the association between FH-Alc and obesity. Self-reports are known to result in underestimated BMI, with effects that may differ by age, gender and measured BMI.52–55 On average, measured BMI is about 0.6 kg/m2 higher than self-report based BMI, and the discrepancy is larger for higher BMI individuals.55 Obesity prevalence estimates based on measurement are up to 50% higher than those based on self-report.56 On the other hand, prevalence estimates of obesity obtained here are quite close to the self-report based estimates produced by the Behavioral Risk Factor Surveillance System survey (BRFSS),57 and BRFSS estimates have exhibited similar secular trends and associations with health outcomes as those based on physical measurement.56, 58 The correlation between measured and self-reported BMI ranges from 0.89 to 0.97, 55,59 and correlation of reporting bias with sociodemographic
