Standard Operating Procedure for External Quality Assessment on Chest X-Ray Interpretation for TB Triage and Diagnosis at Country Level

According to the World Health Organization (WHO), approximately 10 million new TB cases and 1.6 million TB deaths were estimated globally in 2017. In Myanmar, an estimated 191,000 new TB cases and 8,700 cases of multidrug-resistant tuberculosis (MDR-TB) were reported in 2017, with a TB mortality rate of 27,000 deaths annually. Despite a 68% case detection rate in 2017, TB remains a public health challenge in Myanmar. The National Tuberculosis Program (NTP) in Myanmar has achieved a treatment success rate of over 85% for over 10 years, with a strong foundation in TB care and prevention. However, to meet the End TB targets set by the World Health Assembly, Myanmar needs to accelerate efforts to address the determinants of TB, achieve Universal Access, and reduce TB incidence and mortality. TB is considered one of the top three priority diseases in the Myanmar Ministry of Health and Sports National Plan. To strengthen TB diagnosis, the NTP has adopted a strategy to improve the use of chest X-ray (CXR) as a diagnostic tool. CXR has high sensitivity and rapid results, but its low specificity and significant inter-rater variation limit its use. To overcome these limitations, advances in CXR technology have been achieved, including electronically transmitting images, lower operating costs, improved portable systems, and better image quality. The WHO End TB Strategy emphasizes the importance of expanding access to digital CXR services and ensuring quality interpretation of CXR. For this purpose, the Technical Assistance for Management (TeAM) has been selected to design standard operating procedures (SOPs) for external quality assessment (EQA) of CXR interpretation with the collaboration of NTP, USAID/Challenge TB, and WHO. The EQA for CXR interpretation is a planned and systematic approach to monitoring and assessing CXR interpretation at a health facility by an external independent re-reader. The EQA method is based on rechecking CXR samples that have been read at facility level by an independent reference staff. The main benefits of EQA are to use discordant CXR interpretation as a tool for discussion and on-the-job training, to monitor reader performance, to provide early warning to identify problems on CXR interpretation, and to ensure accurate diagnosis of TB and better reliance of TB staff on complementary exams. Designing SOPs for EQA of CXR interpretation in TB triage and diagnosis at country level requires good knowledge of the process of monitoring and evaluation of CXR interpretation rechecking across the health system pyramid. No such EQA activities have yet been carried out in Myanmar on a routine basis. Therefore, a feasibility assessment of the CXR interpretation rechecking involving stakeholders at different levels of the health system pyramid was conducted, and the results were used as a basis to develop this SOP. The CXR interpretation rechecking for TB triage and diagnosis is a process combining implementation of data transfer system and methods for identifying discordant interpretation for reassessment and staff skills mentoring and for measuring inter-rater agreement level between trained readers situated at different levels of the health system. This document presents the procedures of the CXR interpretation rechecking in Myanmar, describing the SOP for EQA for CXR interpretation in TB triage and diagnosis, its objectives, and the methodology of the reassessment. The EQA for CXR interpretation is a critical component of TB control in Myanmar, and its implementation will help to improve the accuracy of TB diagnosis and reduce the burden of TB in the country. The SOP for EQA of CXR interpretation in TB triage and diagnosis at country level will provide a framework for the implementation of EQA activities in Myanmar, ensuring that CXR interpretation is accurate and reliable, and that TB diagnosis is improved.