Piderit, Monique CruzWhite, ZeldaBecker, Piet J.Wenhold, Friedeburg Anna Maria2025-01-212025-01-212024-08Piderit, M. C., White, Z., Becker, P. J., & Wenhold, F. A. M. (2024). Dairy intake screener as web-based application is reliable and valid. Food Science & Nutrition, 12, 5932–5941. https://doi.org/10.1002/fsn3.4187.2048-7177 (print)2048-7177 (online)10.1002/fsn3.4187http://hdl.handle.net/2263/100196DATA AVAILABITY STATEMENT: The dataset used and analyzed during the current study is available from the University of Pretoria on reasonable request.The “Dairy Diary” is a user-friendly web-based dairy intake screener. The reliability and validity are unknown. We aimed to evaluate the screener in terms of test–retest reliability and comparative validity. In a diagnostic accuracy study, a purposefully recruited sample of 79 (age: 21.6 ± 3.8 years) undergraduate dietetics/nutrition students from three South African universities completed 3 non-consecutive days of weighed food records (reference standard) within a seven-day period (comparative validity), followed by two administrations, 2 weeks apart, of the screener (index test) (reliability). For the four dairy product serving scores (PSSs) and the summative dairy serving scores (DSSs) of the screener and the food records, t-tests, correlations, Bland– Altman, Kappa, McNemar's, and diagnostic accuracy were determined. For reliability, mean PSSs and DSSs did not differ significantly (p> .05) between the screener administrations. The mean PSSs were strongly correlated: milk (r= .69; p< .001), maas (fermented milk) (r= .72; p< .001), yoghurt (r= .71; p< .001), cheese (r= .74; p< .001). For DSSs, Kappa was moderate (k= 0.45; p< .001). Non-agreeing responses suggest symmetry (p= .334). For validity, the PSSs of the screener and food records were moderately correlated [milk (r= .30; p= .0129), yoghurt (r= .38; p< .001), cheese (r= .38; p< .001)], with k= 0.31 (p= .006) for DSS. Bland–Altman analyses showed acceptable agreement for DSSs (bias: −0.49; 95% CI: −0.7 to −0.3). Categorized DSSs had high sensitivity (81.4%) and positive predictive value (93.4%), yet low specificity (55.6%) and negative predictive value (27.8%). The area under the receiver operating characteristic curve (0.7) was acceptable. The “Dairy Diary” is test–retest reliable with moderate comparative validity to screen for dairy intake of nutrition-literate consumers.en© 2024 The Author(s). Food Science & Nutrition published by Wiley Periodicals LLC. This is an Open Access article under the terms of the Creative Commons Attribution License.Dairy DiaryDairy intake screenerDietary screenerReliabilityValiditySDG-02: Zero hungerSDG-03: Good health and well-beingArticle