Validity and reproducibility of resting metabolic rate measurements in rural Bangladeshi women:: comparison of measurements obtained by Medgem™ and by Deltatrac™ device

Objective: To assess reproducibility and validity of resting metabolic rate (RMR) of Bangladeshi women as measured with the MedGem device and using the Deltatrac metabolic monitor as a reference; and ( 2) to evaluate the FAO/WHO/UNU basal metabolic rate (BMR)-prediction equations. Design: In each of two sessions, resting oxygen consumption was measured in triplicate by MedGem and in triplicate by Deltatrac device. Setting: Matlab area, the rural field research area of the Centre for Health and Population Research, Bangladesh (ICDDR, B). Subjects: A total of 37 nonpregnant, nonlactating women, aged 27.6 +/- 4.5 y, BMI 20.8 +/- 3.1 kg/m(2) participated. Results: The difference in oxygen consumption by MedGem and Deltatrac device was significantly level dependent. Within-subject within-session variations ( expressed as CV) were 9.0 and 3.0% ( P<0.01) and within-subject between-session variations were 8.2 and 4.5% ( P<0.01) for MedGem and Deltatrac, respectively. Mean RMR measured by Deltatrac (5.17 +/- 0.51 MJ/day) was not significantly different from the BMR predicted by the FAO/WHO/UNU equations (5.16 +/- 0.42 MJ/day) in the second session and only 0.19 MJ/day higher than predicted in the first session (P<0.05). Conclusion: Reproducibility and validity of the MedGem device was poor compared to the Deltatrac reference method. The FAO/WHO/UNU BMR-prediction equations give a good estimation of the BMR of rural, nonpregnant, nonlactating Bangladeshi women of 18 - 35 y.