Accuracy in self-appraisal of body-frame size.

Abstract

A decision as to whether one is overweight is usually obtained by looking at height and weight tables which require a knowledge of sex, height, and body-frame size to determine ideal weight. These tables have been criticized because they have not included an objective procedure for determining body-frame size (1, 3). Tkis lack has been addressed in the 1983 Metropolitan Height and Weight tables by providing individuals with an objective means of estimating body-frame size. Recent mass media presentations of the 1983 tables, however, do not include the recommended procedure for determining body-frame size. It appears that people will continue to make subjective judgments regarding their body-frame size when determining their ideal weights with these tables. This study assessed the accuracy with which people estimate body-frame size when they are not provided an objective means of measurement. Subjects were 85 individuals recmited at a local shopping mall. Forty-five men with a mean age of 30 yr. (SD = 13.66 yr.) and 40 women with a mean age of 31 yr. (SD = 16.55 yr.) were asked to select their ideal weight by examining the 1983 Metropolitan Height and Weight tables. Their selections ~rovided the researchers with a subiective assessment of the subjects' body-frame size. The subjects were then objectively assessed for body-frame size by placing a soft measuring tape around the smallest circumference of the wrist, distal to styloid process of radius and ulna, a procedure developed by Lindner (2). Results indicated only 32 of 85 subjects correctly estimated body-frame size. When the data were examined according to sex, responses of 18 of 45 men and of 14 of 40 women agreed with the Linder criterion. Of the 40 men and 18 women whose data made it possible to underestimate body-frame size, i.e., those subjects with objectively determined medium and large body-frame sizes, 57% of the men and 61% of the women underestimated their body-frame size. As underestimating body-frame size may lead people to believe they are overweight when in fact they may not be, the incidence of underestimating observed here may help explain surveys which yield a much higher incidence of subjective feelings of being too fat than would be warranted by objective estimates.