Assessment of Diagnostic Accuracy for Hepatitis B Virus in Regional Diagnostic Laboratories

Thesis Abstract

Hepatitis B virus (HBV) remains a significant global health challenge, particularly in resource-limited settings where diagnostic accuracy and reliability of laboratory testing are critical for effective disease management and control. Despite the availability of various diagnostic assays, discrepancies in test performance across regional diagnostic laboratories may compromise case detection, leading to misdiagnosis and inadequate patient care. This study aims to assess the diagnostic accuracy of HBV detection methods employed in regional laboratories, with specific objectives to evaluate the sensitivity, specificity, and concordance of diagnostic assays, identify factors influencing test performance, and propose quality improvement interventions. Utilizing a cross-sectional analytical design, the study was conducted across five regional diagnostic laboratories servicing urban and peri-urban populations. The study population comprised 300 serum samples collected from confirmed HBV-positive and HBV-negative patients according to national clinical criteria. Samples were randomly selected and subjected to parallel testing using commonly employed assays, including enzyme-linked immunosorbent assays (ELISAs), rapid diagnostic tests (RDTs), and polymerase chain reaction (PCR) techniques. Data collection instruments included standardized laboratory data sheets, quality control logs, and structured questionnaires capturing laboratory staff competencies, equipment status, and procedural adherence. To determine diagnostic accuracy, results from various assays were compared against a reference standard—quantitative PCR—considered the gold standard in HBV detection. The validity and reliability of data were ensured through calibration of equipment, double data entry, and staff training. Data analysis involved descriptive statistics to summarize assay performance, and inferential statistics including sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and Cohen’s kappa coefficient assessed concordance between tests. Logistic regression models identified predictors of diagnostic accuracy, while Receiver Operating Characteristic (ROC) curve analysis evaluated the discriminative power of assays. Theoretical underpinning was based on the Quality Assurance Framework and the Theory of Laboratory Quality Management Systems. It is anticipated that the study will reveal variable diagnostic performance across laboratories, with some assays demonstrating suboptimal sensitivity and specificity, particularly in low-resource settings. Factors such as inadequate staff training, equipment calibration, and supply chain disruptions are expected to significantly influence test outcomes. The findings are projected to highlight the critical gaps in current diagnostic practices, underscoring the need for standardized protocols, capacity building, and quality assurance measures. The study’s contribution to knowledge lies in providing evidence-based insights into the performance of HBV diagnostic tests in a real-world context, informing policy formulation, and guiding laboratory practice improvements. Furthermore, the research will establish a diagnostic accuracy benchmark, facilitating continuous quality improvement initiatives within regional laboratories. The main conclusion will emphasize that ensuring high diagnostic accuracy is essential for effective HBV control, and targeted interventions are needed to address identified deficiencies. Recommendations will include the implementation of routine external quality assessment schemes, training programs for laboratory personnel, regular maintenance of diagnostic equipment, and procurement strategies aligned with assay validation standards. The study advocates for strengthening laboratory networks to promote standardized practices and consistent quality assurance, ultimately improving HBV detection and management at regional levels. Future research directions may explore the longitudinal impact of quality improvement interventions on diagnostic performance, as well as expanding investigations to include emerging molecular diagnostics in HBV testing.