Background: Dengue fever (DF) is a significant public health issue in Asia. We aimed to use clinical and laboratory data to derive a rapid and accurate case-finding tool for DF in children.Methods: This retrospective study used 24 DF-related characteristics and clinical features (17 clinical; 7 laboratory) of 177 pediatric patients (69 diagnosed with DF). Data were psychometrically evaluated using a Rasch measurement model, and their values for predicting DF risk were evaluated.Results: The 14-item scale (DF-14) fit the measurement model in assessing the likelihood of DF. When a cutoff point of -1.15 (in logit) of the DF-14 scale was used, the sensitivity was 0.76 and the specificity was 0.76. The area under the curve was 0.93 (95% confidence interval: 0.89-0.97). The DF-2 scale, comprised of white blood cell and platelet counts, was simple but clinically useful.Conclusions: Simple laboratory data, such as those in the DF-2 and DF-14 scales, are useful for the early detection of DF risk in children. The DF-14 scale helps discriminate DF from other febrile illnesses and may eliminate the need for a costly and time-consuming dengue confirmation test.