ObjectiveThe aim of the present study was to identify all currently available screening and assessment tools for detection of malnutrition in hospitalised children, and to identify the most useful tools on the basis of published validation studies.DesignSystematic review.Data sourcesPubMed, CINAHL and MEDLINE were searched up to October 2017.Eligibility criteria for selecting studiesStudies in English that reported sensitivity, specificity and positive/negative predictive values (PPVs/NPVs) in the paediatric population were eligible for inclusion.Data extraction and synthesisTwo authors independently screened all of the studies identified, and extracted the data. The methodological qualities of the studies included were assessed using the Quality Assessment of Diagnostic Accuracy Studies-2 tool.ResultsThe 26 validation studies that met the inclusion criteria for this systematic review used eight screening and three assessment tools. The number of participants varied from 32 to 14 477. There was considerable variability in the chosen reference standards, which prevented direct comparisons of the predictive performances of the tools. Anthropometric measurements were used as reference standards in 16 of the identified studies, and full nutritional assessment in 5. The Pediatric Yorkhill Malnutrition Score (PYMS) screening tool performed better than Screening Tool for the Assessment of Malnutrition and Screening Tool for Risk On Nutritional status and Growth when compared in terms of anthropometric measurements, especially for body mass index (Se=90.9, Sp=81.9) and triceps skinfold thickness (Se=80.0, Sp=75.0). However, low PPVs indicated the problem of overprediction of positive cases, which was typical for all of the studies that used anthropometric measurements as the reference standard.ConclusionsThis systematic review identifies the need for definition of the gold standard for validation of screening tools. Anthropometry measurements using WHO or Centers for Disease Control and Prevention growth charts should be considered as the possible reference standard in future validation studies. We would recommend the use of PYMS for hospitalised paediatric patients without chronic conditions, in combination with full nutritional assessment.PROSPERO registration numberCRD42017077477.