Main Organiser

Julius Centre University of Malaya

Co-organiser

Department of Social and Preventive Medicine, Faculty of Medicine, University of Malay

Supported by

University of Malaya

HOW RELIABLE IS A PATIENT'S PERCEIVED AND SELF REPORTED WEIGHT AND HEIGHT: AN ASIAN EXPERIENCE

Author

Aris JH, Chia YC, Kulenthran A

Institution

University of Malaya

Abstract

Objectives: To assess the concordance between one, a person’s perception of their weight status (BMI) and his actual BMI and two, the concordance between a person’s self-reported BMI (computed from his self-reported height and weight) and his actual BMI (computed from his measured weight and height)

Methods: 352 patients from a Primary Care Department were first asked if they felt they were underweight, normal, overweight or obese to determine their self perception of weight status. They were next asked what their weight and height was to determine their self-reported values. Having received the information, their height and weight was then measured to determine their actual values. These parameters were then computed to classify their obesity index (Kg / height2 in meters) as follows: < 18.5 = underweight; 18.5 to 22.9= normal; 23 to 27.4 = overweight and > 27.5 = obese. For non-Asians the following criteria was used: < 18.5 = underweight; 18.5 to 24.9= normal; 25 to 29.9 = overweight and > 30 = obese. The kappa statistic was used to assess the concordance between their self- perceived and actual status.

Results: While their perception of their BMI revealed only fair concordance (kappa 0.33), the self reported BMI showed good concordance with their actual values (kappa 0.75). Being Chinese, unemployed and having co-morbidities gave better concordance but being poorly educated and being a foreigner gave poor concordance

Conclusion: The results suggest that firstly, a patient’s perception of their own weight status is not reliable. Secondly, a patient’s self-reported BMI based on their reported height and weight is reliable and provides as a surrogate marker to measure their BMI.