A field tool for prediction of body fat in Sri Lankan women: skinfold thickness equation

Abstract

BackgroundValid skinfold thickness (SFT) equations for the prediction of body fat are currently unavailable for South Asian women and would be a potentially robust field tool. Our aim was to assess the validity of existing SFT equations against deuterium (2H2O) dilution and, if invalid, to develop and validate an SFT equation for % fat mass (%FM) in Sri Lankan women.MethodsH2O dilution was used with Fourier transform infrared (FTIR) spectroscopy as the criterion method for the assessment of %FM in urban Sri Lankan women (30–45 years). This data was used to assess the validity of available SFT equations and to generate and validate a new SFT equation for the prediction of %FM against the criterion method. Women (n = 164) were divided into validation and cross-validation groups for the development and validation of the new equation. The level of agreement between the %FM calculated by the final derived prediction equation and the %FM obtained by 2H2O dilution was assessed using Pearson’s correlation coefficient (R) and Bland Altman plots. Student’s t test was used to assess over- or underestimation, and significance was set at p < 0.05.ResultsExisting equations significantly (p < 0.001) underestimated %FM compared with the 2H2O dilution method. The final equation obtained was %FM = 19.621 + (0.237*weight) + (0.259*triceps). When compared with 2H2O dilution, %FM by the equation was not significantly different. There was a significant (p < 0.001) correlation between %FM by the reference method and %FM by the equation. The limit of agreement by Bland Altman plot was narrow with a small mean positive bias.ConclusionsExisting SFT equations were not applicable to this population. The new equation derived was valid. We report a new SFT equation to predict %FM in women of South Asian ancestry suitable for field use.

Body fat and lipid parameters of management assistants in a rural area in Sri Lanka

“…In the present study, for the same age group of women, comparable results were obtained [mean age 34.2(3), BMI 24.9(4.1), BF% 35.2(3.9)]. Furthermore, that study elucidated that the fat mass percentages calculated by applying Density (obtained by Durnin and Womersley equation) to Siri and Brozeket al equations and to the equation developed by de Lanerolle-Dias et al significantly (p < 0.001) underestimated %FM compared to the 2 H2O dilution 23 .…”

Development and Cross-Validation of Anthropometric Predictive Equations to Estimate Total Body Fat Percentage in Adult Women in Sri Lanka

“…is might be due to that postmenarcheal girls have less body fat compared to the women in reproductive ages and beyond which limits the applicability of equations to women in a wider age range. erefore, an attempt has been made to develop an equation for middleaged women, and this equation includes only the TrSFT and weight [8].…”

“…However, radiation exposure and relatively high cost have restricted its availability. Equations that estimate TBFP based on simple anthropometric measurements such as weight, height, SFTs, and circumferences may overcome this shortcoming since they are simple, inexpensive, and practical [8].…”

“…It is essential that country/ethnic-specific equations to estimate fat mass should be developed based on local data. Although two equations have been developed for Sri Lankan women for this purpose, they have focused only the adolescent girls [12] and women with a narrow age range (30-45 years) [8].…”

“…These equations, however, need calculation of body density prior to TBFP calculation. Further, they have been shown to be invalid in the Sri Lankan context [ 8 ] since the proportions of body segments depend not only on weight, age, and gender but also on the ethnicity, genetics, and lifestyle.…”