Effect of perioperative glutamine-enriched nutritional support on patients with colorectal cancer: A systematic review and meta-analysis

Table 1 Data sources and search strategy

Data sources	Search strategy
PubMed, EMBASE, Web of Science, Cochrane Library, Chinese Biomedical Database, CNKI, VIP, and Wanfang Electronic Database	"Rectal Neoplasms," "Colorectal Neoplasms,” "Colonic Neoplasms,” "Glutamine," and "randomized controlled trial" as subject terms combined with their corresponding free words for all possible combinations. Search terms were combined using the Boolean operators "AND" and "OR"
Others	Additional articles were manually searched in the reference lists of articles selected for the full-text search. For overlapping authors, institutions, or patients, the most recent or highest-quality articles were selected