Physicians' diagnosis of obesity status in NHANES II

The aim of this work was to assess the accuracy of physicians' subjective assessments of obesity status. The subjects were participants in The Second National Health and Nutrition Examination (NHANES II) Survey. The physicians' subjective judgments of obesity were compared to BMI, an objective measure of actual body mass. Subjects with a body mass index (BMI = weight in kg/(height in cm/100)2) less than or equal to 27.5 were classified as normal weight and those with a BMI greater than or equal to 30.4 were considered to be obese. Physicians were accurate in their diagnosis of the normal weight group with only 4.03% being misdiagnosed as obese. However, 12.6% of the obese group was misdiagnosed as normal weight. The odds of an incorrect normal weight diagnosis increased with age. Similarly, as the fat distribution ratio increased, i.e., a more central pattern, the odds of being actually obese but incorrectly diagnosed as normal weight increased. Men were more likely than women to be incorrectly diagnosed as normal weight. Non-Caucasian normal weight persons appear to have been diagnosed more stringently than Caucasians as they were more likely to be misdiagnosed as obese regardless of their gender. There appear to be several variables affecting the physicians' subjective assessment of obesity status in this data set.