Self‐reported vs. Measured Height and Weight in Young Adults

Abstract

IntroductionObesity is recognized as a worldwide public health concern. It is most commonly assessed and classified using Body Mass Index (BMI). Historical data says that adults tend to under‐report their own weight and that the gap between self‐reported weight and actual weight increases with obesity. Few studies have examined how well young adults report their own height and weight.ObjectiveThis study investigates self‐reported height, weight and subsequent BMI versus actual measurements in young adults.MethodsOver 1,500 students across 8 U.S. universities provided their height and weight via a survey. Measurements were subsequently taken by trained professionals; both self‐reported and measured BMI were then calculated for each participant. Correlations between self‐reported and measured BMI were assessed using Spearman's rho. Kappa coefficient was used to test agreement between categorical variables of self‐reported and actual calculated BMI (i.e. underweight, normal, overweight, obese).ResultsMale and female students both underestimated their height, with males overall under‐reporting more than males. Males reported an average height of 166.4 ± 12.1 cm versus an actual average height of 175.3 ± 7.8. Females reported an average height of 157.1 ± 7.2 cm versus an actual average height of 164.6 ± 7.1 cm. Males slightly overestimated their weight, with an average self‐reported weight of 76.8 ±14.5 kg versus an actual average weight of 76.2 ± 15.7 kg. Females slightly underestimated their weight with an average self‐reported weight of 65.2 ± 14.4 kg versus an actual average weight of 65.7 ± 15.3 kg. However, the self‐reported measurements remained statistically correlated to the actual height, weight and BMI in both genders (males rs = 0.79, <0.0001, rs = 0.91, <0.0001 and rs = 0.83, <0.0001 respectively; females rs = 0.78, <0.0001, rs = 0.91, <0.0001 and rs = 0.76, <0.0001 respectively). Additionally, categorical variables of BMI from both self‐reported and actual height and weight resulted in significant agreement for both genders (Males κ = −0.09 (95% CI, −0.12 to −0.04), p < .0001; Females κ = −0.04 (95% CI, −0.07 to −0.01), p = .004).ConclusionsThis study suggests self‐reported anthropometric measurements in young adults can be used to calculate BMI for weight classification purposes. Further investigation is needed to better assess self‐reported vs. measured height and weight discrepancies across populations.Support or Funding InformationApproval to use the data set was granted by the University of Tennessee Institutional Review Board prior to study implementation. This material is based upon work that is supported by the National Institute of Food and Agriculture, U.S. Department of Agriculture, under award number 2014‐67001‐21851.