title: A field tool for prediction of body fat in Sri Lankan women: skinfold thickness equation.
abstract: Valid 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.
  
  
  
  H2O 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 by2H2O 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.
  
  
  
  Existing equations significantly (p < 0.001) underestimated %FM compared with the2H2O dilution method. The final equation obtained was %FM = 19.621 + (0.237*weight) + (0.259*triceps). When compared with2H2O 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.
  
  
  
  Existing 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.
authors.affiliation: Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Colombo, Kynsey Road, Colombo 8, Sri Lanka.
authors.forename: Indu
authors.initials: I
authors.lastname: Waidyatilaka
authors.affiliation: Department of Physiology, Faculty of Medicine, University of Colombo, Kynsey Road, Colombo 8, Sri Lanka.
authors.forename: Angela
authors.initials: A
authors.lastname: de Silva
authors.affiliation: Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Colombo, Kynsey Road, Colombo 8, Sri Lanka.
authors.forename: Maduka
authors.initials: M
authors.lastname: de Lanerolle-Dias
authors.affiliation: Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Colombo, Kynsey Road, Colombo 8, Sri Lanka.
authors.forename: Sunethra
authors.initials: S
authors.lastname: Atukorala
authors.affiliation: Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Colombo, Kynsey Road, Colombo 8, Sri Lanka. pulanil@yahoo.co.uk.
authors.forename: Pulani
authors.identifier: 0000-0002-1204-3740
authors.initials: P
authors.lastname: Lanerolle
mesh_terms: D000273:Adipose Tissue; D000328:Adult; D044466:Asian People; D001823:Body Composition; D001835:Body Weight; D003903:Deuterium; D005260:Female; D006801:Humans; D055641:Mathematical Concepts; D008875:Middle Aged; D008954:Models, Biological; D009765:Obesity; D012016:Reference Values; D012885:Skinfold Thickness; D017550:Spectroscopy, Fourier Transform Infrared; D013188:Sri Lanka; D014867:Water
chemical_list: D014867:Water; D003903:Deuterium
keywords: Asian; Body composition; Body fat; FM; Fat mass; SFT; Skinfold thickness