Clinical assessment and biomarkers for the detection of bacterial community-acquired pneumonia in children and adults: a protocol for systematic review of diagnostic accuracy

Community-acquired pneumonia (CAP) is defined as an infection of the pulmonary parenchyma acquired in the community and outside the hospital setting. CAP is generally diagnosed based on clinical parameters and chest radiography, with biomarkers increasingly used to support diagnostic decisions. Our review aims to synthesise evidence on the diagnosis of bacterial CAP using clinical assessments and biomarkers and to guide evidence-based national antibiotic guidelines for bacterial CAP in India. Our primary objective is to determine the diagnostic accuracy of clinical criteria (symptoms, examination findings, or clinical scoring systems) and chest X-rays with and without serum biomarkers for detecting bacterial CAP in children and adults with presumptive signs and symptoms of pneumonia. We also aim to investigate potential sources of heterogeneity in the diagnostic accuracy of the aforementioned index tests in relation to covariates such as the healthcare settings, HIV status, malnutrition, and comorbidities. We will perform a systematic search of electronic databases without language and geographical restriction and bibliography mining. We will only include prospective and retrospective cross-sectional and cohort studies and Randomized Control trials. We will exclude case reports, conference abstracts, reviews, and studies with a case-control design. We will also include studies that provide or allow the derivation of diagnostic accuracy data. Participants from all healthcare settings with a presumptive diagnosis of CAP will be included. The QUADAS-2 tool will be used to ascertain the methodological quality of the selected studies. We will perform analyses of data for children and adults separately. Bivariate model will be used for meta-analysis to estimate summary sensitivity and specificity wherever possible. Certainty of evidence will be assessed using the GRADE approach (Grading of Recommendations Assessment, Development, and Evaluation) for diagnostic test accuracy studies. Our review will evaluate the diagnostic accuracy of clinical criteria, with and without biomarkers, for diagnosing bacterial CAP in children and adults. This will inform antibiotic guidelines in India and similar resource-limited settings. PROSPERO CRD42024619430 and CRD42024620335