• Unaib Rabbani Department of Community Health Sciences, Aga Khan University, Karachi
  • Assad Ahmed Nafees Department of Community Health Sciences, Aga Khan University, Karachi


Background: The purpose of this study was to compare lung function of textile workers with healthy Pakistani population, compare predicted values based on the European Respiratory Society (ERS) equations with those based on the Pakistani equations, and to develop predictor equations for textile workers in Pakistan. Methods: This was a secondary analysis of data from two previous surveys where lung function of textile workers was compared with healthy Pakistani men. Spirometry was performed according to the American Thoracic Society guidelines. Independent sample t-test was used to compare the lung function parameters and multivariate linear regression was used to develop predictor equations. Results: There were significant differences in lung function of textile workers (FVC: 4.1 L, FEV1: 3.3 L and FEV1/FVC: 0.8) compared to healthy Pakistani men (FVC: 3.9 L, FEV1: 4.1 L and FEV1/FVC: 1.04). ERS reference equations tended to under-diagnose abnormal lung function, 16.9 % versus 25.3% (p<0.01). Predictor equations for Pakistani textile workers were also developed. Conclusion: Lung function of textile workers was significantly reduced compared to healthy population. Use of ERS reference equations for Pakistani textile workers may not provide appropriate interpretation.Keywords: Textile Industry workers; Spirometry; Lung function prediction equations; European Respiratory Society (ERS) prediction equations;Pakistan


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