Selection Process and Data Extraction Process
The titles and abstracts of all the retrieved articles were independently analyzed by two reviewers, and a third reviewer solved instances of disagreement. Articles whose abstracts did not provide sufficient information were selected for full-text analysis. Following selection based on titles and abstracts, the same reviewers independently selected articles based on full-text analysis. Data extraction was performed in duplicate by the same two reviewers, and a third reviewer solved instances of disagreement, who used a standardized form for this purpose. The following data were extracted: authors, year of publication, country of the research, study design, sample size, prematurity categorization, assessment tool, DCD criteria cut-off point, and prevalence of DCD.