Diagnostic accuracy of chest x-ray in covid -19, taking high resolution computed tomography as gold standard

Objective: To determine sensitivity & specificity of chest X-ray in COVID-19, taking High-Resolution Computed Tomography as gold standard. Study Design: Cross-sectional study. Place and Duration of Study: Radiology Deptt, Margalla Hospital, Taxila and Islamabad Diagnostic Centre, Wah. Two years (February 2020 to February 2022). Patients and Methods: The sample comprised 100 COVID-19 patients (Positive Polymerase chain reaction (PCR) test). Their HighResolution Computed Tomography (HRCT) was done which was considered a gold standard for diagnosing COVID-19. Their Chest X-rays (CXR) were performed, and findings of both modalities were compared. Patients having respiratory tract symptoms but PCR negative for COVID-19 were excluded. Results: The research had 49 males & 51 females having a median (IQR) age of 46.50(35-55.75) years. The minimum & maximum ages were 6 years and 83 years respectively. Among 100 PCR-positive patients, 29 were found normal on HRCT and 30 on CXR. For moderate cases, the chest X-rays were 72% sensitive & 90.67% specific, with Positive Predictive Value (PPV), Negative Predictive Value (NPV) & diagnostic efficacy of 72%,90.67% & 86% respectively. Similarly, other severity levels were assessed. Conclusion: CXR has acceptable diagnostic accuracy for COVID-19 patients, especially with good sensitivity for moderate cases and better specificity for severe cases. A portable chest radiograph might be regarded as an initial alternative imaging modality for patients with COVID-19 signs and symptoms in remote areas.