Abstract:
Objective: To determine diagnostic accuracy of chest x-ray for the diagnosis of interstitial lung disease keeping high resolution computed tomography as gold standard.   Study design and setting: Comparative cross sectional study, Department of Radiology PNS Shifa Karachi Methodology: Study done over the period of 1 year and two months. 160 Patients were included by using non-probability consecutive sampling all underwent CXR and HRCT chest. Sample size was calculated using sensitivity and specificity calculator for sample size with expected sensitivity of 80%7, expected specificity of 82.98%7and expected prevalence of 76%7   Results: In this 160 patients were included by using non probability sampling. Among all 116(72.50%) were males while 44 (27.50%) were females. Sensitivity (SE),specificity, positive predictive value (PPV) negative predictive value(NPV) and diagnostic accuracy of CXR vs HRCT in cases of ILD was 88.89%, 87.50%, 88.89%, 87.50% and 88.24% respectively.   Conclusion: Chest x-ray has high diagnostic accuracy and simultaneously readily available and cost effective modality, therefore it can be effectively used as alternative to HRCT.