Decoding community-acquired pneumonia: a systematic review and analysis of diagnostic criteria and definitions used in clinical trials

Abstract

Background

Community-acquired pneumonia (CAP) is a frequent and potentially life-threatening condition. Even though the disease is common, evidence on CAP management is often of variable quality. This may be reinforced by the lack of a systematic and homogeneous way of defining the disease in randomized controlled trials (RCTs).

Objectives

This study aims to assess the diagnostic criteria and definitions of the term ‘community-acquired’ used in RCTs on CAP management.

Data sources

On the basis of the protocol (PROSPERO 2019 CRD42019147411), we conducted a systematic search of Medline/PubMed and the Cochrane Register of Controlled Trials for RCTs published or registered between 2010 and 2024.

Study eligibility criteria

Study eligibility criteria included completed and ongoing RCTs.

Participants

Participants included adults hospitalized with CAP.

Methods of data synthesis

Data were collected using a tested extraction sheet, as endorsed by the Cochrane Collaboration. After cross-checking, data were synthesized in a narrative and tabular form.

Results

In total, 7173 records were identified through our searches. After removing records that did not fulfil the eligibility criteria, 170 studies were included. Diagnostic criteria were provided in 69.4% of studies, and the term ‘community-acquired’ was defined in 55.3% of studies. The most frequently included diagnostic criteria were pulmonary infiltrates (94.1%), cough (78.8%), fever (77.1%), dyspnoea (62.7%), sputum (57.6%), auscultation/percussion abnormalities (55.9%), and chest pain/discomfort (52.5%). The different criteria were used in 87 different sets across the studies. The term ‘community-acquired’ was defined in 57 different ways.

Conclusions

The diagnostic criteria and definitions of CAP in RCTs exhibit significant heterogeneity. Standardizing these criteria in clinical trials is crucial to ensure comparability across studies.