Jariya ChuthapisithPornchanok WantanakornRawiwan RoongpraiwanMahidol University2018-11-232018-11-232015-01-01Journal of the Medical Association of Thailand. Vol.98, No.8 (2015), 748-75501252208012522082-s2.0-84939526703https://repository.li.mahidol.ac.th/handle/20.500.14594/36724© 2015, Medical Association of Thailand. All rights reserved. Objective: To develop a parental questionnaire for screening children with delayed language development in primary care settings. Material and Method: Ramathibodi Language Development (RLD) questionnaire was developed and completed by groups of 40 typically developing children age 18 to 30 months old and 30 children with delayed language development. Results: The mean score was significantly lower in the delay language group (6.7±1.9), comparing with the typically developing group (9.6±0.7). The optimal ROC curve cut-off score was 8 with corresponding sensitivity and specificity were 98% and 72%, respectively. The corresponding area under the curve was 0.96 (95% CI = 0.92-0.99). Conclusion: The RLD questionnaire was the promising language developmental screening instrument that easily utilized in well-child examination settings.Mahidol UniversityMedicineArticleSCOPUS