Background & aims: A valid, quick-and-easy screening tool to detect undernutrition, is an essential requisite to treat undernutrition. In order to select quick-and-easy screening tools with high analytical accuracy for the general hospital in-, and outpatient population, a systematic review at sensitivity and specificity studies were performed. Methods: The electronic databases MEDLINE, EMBASE, CINAHL and the Cochrane Library (SR, DARE and the Central trail register) were searched. Additionally, ESPEN and ASPEN congress posters and abstracts from 2000 till 2005, reference lists and review articles, were hand-searched. There were no limitations made on language or publication date. To finally include a study there were six criteria: The study (1) determined analytical accuracy of a quick-and-easy screening tool in (2) adults with (3) the dichotomous classification: disease-related undernutrition present or absent, versus (4) an acceptable reference standard with (5) data available to abstract sensitivity and specificity. Methodological quality was formally assessed using the QUADAS (checklist for quality assessment in analytical accuracy studies) in those studies with (6) relevant sensitivity and specificity. Results: The search yielded 1513 citations of which finally, nine studies were included. After quality assessment, no studies for the general hospital outpatient population remained. For the general hospital inpatient population only the Short Nutritional Assessment Questionnaire (SNAQ) and the Malnutrition Screening Tool (MST) tool were studied with a high rating to the criteria specified. The analytical accuracy of the MST seemed slightly better than the SNAQ. However, the MST study had a lower QUADAS 'score' for blinding and the cut-off point of the MST for positive screening was defined post-hoc. Conclusion: Their high applicability combined with clinically relevant sensitivity and specificity make the MST and the SNAQ the most accurate nutritional screening tools ready to implement at the general hospital inpatient population found in our systematic review.