xix, 198 p. : ill. A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number. / Due to the lack of a screening and early identification system, preschool children who live in rural areas in Northeast Thailand have no opportunity to receive specialized educational services. Most children are identified as having disabilities at school age or older. In this study, the 24-, 30-, and 36-month intervals of the Ages and Stages Questionnaires (ASQ), a parent-completed screening system, were translated and evaluated for reliability and use in Northeast Thai early childcare settings. The study purpose was to investigate the reliability and utility of the Ages and Stages Questionnaires: Thai (ASQ: Thai). Reliability studies included an investigation of internal consistency, test-retest reliability, interobserver reliability, and comparison of differences between U.S. and Thai scores. Utility studies included surveys of satisfaction of parents/caregivers and early childcare staff as well as brief interviews with parents/caregivers and early childcare staff. Subjects included 267 children who were 2-3 years old; 267 parents/caregivers; 49 early childcare staff; and 5 early childcare professor experts. The subjects were recruited through the Department of Curriculum and Instruction, the Faculty of Education, Mahasarakham University. Results addressing the reliability and use of ASQ: Thai were promising. Internal consistency (ρ = .58 -.89) results were adequate as well as test-retest agreement (ρ > .90). A comparison between the ASQ: Thai sample data and the U.S. normative sample found that there were some differences in range, mean, median, interquartile range, and cutoff scores. The back translation of the ASQ: Thai appeared to be adequate in comparison to the original version, as well as culturally appropriate. Early childcare staff and parents/caregivers felt that the ASQ: Thai was easy to use and understand and was culturally appropriate, and they gained knowledge about child development. Early childcare staff and parents/caregivers suggested that the ASQ: Thai should be used in early childcare settings with children when they enter the program. Future research on the ASQ: Thai is needed. Increased study of cultural, language, and disability issues are areas for further study. / Committee in charge: Jane Squires, Chairperson, Special Education and Clinical Sciences; Deanne Umuh, Member, Special Education and Clinical Sciences; Erin Barton, Member, Special Education and Clinical Sciences; Kathie Carpenter, Outside Member, International Studies