The objective of this Inter-Agency Agreement is to develop a hearing examination protocol to implement hearing tests in the Early Childhood Longitudinal Study of the Kindergarten Class of 2010?11. This is a large (n=20,000), nationally representative school-based exam and interview survey sponsored by the National Center for Education Statistics (NCES), U.S. Department of Education. The last NCES longitudinal cohort study of school age children began with the 1998 Kindergarten Class. In this earlier cohort, there were no hearing exams (nor vision exams) and the number of young children with hearing loss (reported by parents or teachers) shrank considerably after the initial enrollment of Kindergarteners. In the U.S., the last comprehensive national study of children with hearing exam measures was the 1963?1965 National Health Examination Survey (NHANES predecessor) for children aged 6 to 11 years. The Epidemiology Branch, NEI, is sponsoring development of a vision exam protocol to be used in conjunction with the hearing exam protocol. Visual refractive error will be tested with the automated objective refraction device, Retinomax K-plus 2, using the manufacturer's directions. When children are identified with hearing (or vision) loss early in the study, they will be included in a ?selected? (protected) subsample for more intensive tracking in follow-up waves of the survey. Children in the selected subsample will be tracked to new schools if they are subsequently enrolled in a school that was not in the original school sample, e.g., when families relocate. In addition to hearing and vision, the ECLS-K:2010-11 will track several other outcome measures (e.g., general health, social and physical development, achievement scores, and communication problems) associated with educational performance. Hearing and vision will be tested when the children are examined in the school setting. NCES has awarded a contract to WESTAT to conduct the field operations, including selection of sample schools, data collection, and preparation of user-friendly research data files. The contractor will obtain measures of hearing sensitivity, middle ear function, and visual refractive errors of Kindergartners once during the Kindergarten year. Hearing thresholds will be recorded from each ear separately. In addition, the contractor will obtain tympanometric traces to assess middle ear function.