Does BMI Generated by Self-Reported Height and Weight Measure Up in Older Adults? Associations between Self-Report and Measurement in Six Middle Income Countries from the Study on Global AGEing and Adult Health (SAGE)

Theresa E. Gildner, University of Oregon
Tyler Barrett, University of Oregon
James J. Snodgrass, University of Oregon

Individuals often overestimate their height and underestimate their weight, resulting in lower obesity prevalence rates when self-report (SR) data are used to calculate BMI. Measured weight and age also appear to influence the accuracy of SR BMI values. It is unclear if SR accuracy varies cross-culturally. Data from China, Ghana, India, Mexico, the Russian Federation, and South Africa were used to examine discrepancies between SR and actual BMI among older adults. Paired t-tests assessed differences between SR and measured BMI values by country. Linear regressions examined the contribution of age and measured weight to differences between SR and measured BMI. Significant differences exist between reported and measured BMI values (p < 0.05); these differences vary by country, sex, and age group. Measured weight significantly contributed to differences between SR and measured BMI in China and Russia (p < 0.001). Age contributed an insignificant amount to variation in BMI discrepancy.