Diagnostic agreement between the Global Leadership Initiative on Malnutrition criteria and Subjective Global Assessment for preoperative malnutrition in adults undergoing elective surgery: a systematic review and meta-analysis

Protein-energy malnutrition remains frequently unrecognised, under-reported, and undertreated in surgical populations despite being associated with a higher risk of postoperative complications. This systematic review evaluated the diagnostic agreement between the Global Leadership Initiative on Malnutrition (GLIM) operational criteria and the Subjective Global Assessment for identifying adults at risk of preoperative protein-energy malnutrition undergoing elective surgery. MEDLINE, Embase, CINAHL, and Web of Science were searched from inception to 5 May 2025. Substantial heterogeneity was observed across eight included studies ( n =5834) in the definitions, cut-offs, and measurement methods for GLIM phenotypic and aetiologic criteria. In six noncardiac surgical studies ( n =3999), pooled sensitivity and specificity were 76% (95% confidence interval [CI] 69–81%) and 88% (95% CI 77–94%), respectively, using a random-effects bivariate model (very low certainty of evidence). Overall diagnostic agreement was fair; thus, the GLIM criteria alone may be insufficient to make the diagnosis of malnutrition and to guide nutritional interventions without additional clinical or dietetic assessment.