Discrepancy between subjective and objective measures of obesity amongst the undergraduate medical and dental students: an institution-based cross-sectional study

Abstract

Background: Obesity has been reported to be assessed both subjectively and objectively, with varying degrees of agreement. This study was conducted to assess the discrepancy between the subjective and objective measures of obesity amongst undergraduate medical and dental students.

Methods: A cross-sectional study was designed and conducted at College of Medical Sciences and Teaching Hospital, Nepal, from December 2019 to January 2020. First and second year under­graduate medical and dental students were first asked to report their height and weight, which were subsequently measured using standard stadiometer and weighing balance. Body mass index (BMI) was calculated from both subjective and objective height and weight, and was graded into different categories as underweight, normal, overweight and obese.

Results: Of the 181 participants, 51.4% were males. The prevalences of subjective and objective overweight/obesity were 24.8% and 25.4%, respectively, with the difference being –0.6% (95% CI: –9.5% to 8.4%; p>0.05). Likewise, the differences in prevalence rates were +4.3% (95% CI: –8.6% to 17.2%; p>0.05) in males and –5.7% (95% CI: –17.9% to 6.6%; p>0.05) in females. Further, the differences between the mean values of subjective and objective BMI were +0.4kg/m2 (p=0.086, overall); +0.9kg/m2 (p=0.002, males) and –0.3kg/m2 (p=0.122, females).

Conclusions: In the face of varying degrees of discrepancy between subjective and objective mea­sures of obesity in overall participants as well as in both gender groups, the findings suggest a reasonable degree of acceptability of the subjective assessment.