Systematic search and strategy
The meta-analysis was carried out by the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA)[9]. After inception and before May 2022, PubMed, Embase, Web of Science, EBSCO, Cochrane, Scopus, and CNKI were among the databases searched for relevant articles. The search strategy addressed two of five elements of the PICOS model (Population, Intervention/Exposure). Using Boolean operators, the search technique merged two areas as MeSH terms, keywords, and text words: (”Caffeine Citrate” OR ”Caffeine” OR ”Citrates”) AND (Apnea) AND (”Preterm Infants” OR ”Infant, Premature” OR ”Very Low Birth Weight Infants ” OR ” Infant, Low Birth Weight ” OR ” Neonatal Prematurity”)