Time-to-Positivity of Blood Cultures as a Predictor of Clinical Outcome: A Systematic Review and Meta-Analysis

Background: Time-to-positivity (TTP) of blood cultures reflects pathogen burden and growth kinetics and has been proposed as a prognostic indicator in bloodstream infections (BSIs). However, the extent to which TTP predicts clinical outcomes remains uncertain. Objectives: To systematically evaluate the association between TTP and adverse clinical outcomes, including mortality, illness severity, ICU admission, and persistent bacteremia. Methods: A systematic review and meta-analysis was conducted in accordance with PRISMA 2020 guidelines. PubMed, Embase, Scopus, Web of Science, and Cochrane Library were searched from inception to June 2025. Observational and interventional studies reporting outcomes stratified by TTP were included. Risk of bias was assessed using the Newcastle–Ottawa Scale, and random-effects models were applied for pooled analyses. Results: Twenty-three studies comprising diverse adult and pediatric cohorts were included. Shorter TTP (commonly