The 2-year study evaluated the language performance of 69 hearing impaired, preschool children born following the rubella epidemic of the early 1960's in order to develop an instrument for objectively assessing language achievement and a predictive index of language achievement. Two language rating scales were developed which were tied to the specific curriculum used in the program and measured only oral language reception and expression. The scales were found to be valid instruments for the particular group of hearing impaired Ss assessed. Major factors found to be significant predictors of language performance were home environment (particularly the mother-child relationship), creativity, degree of hearing impairment, prematurity, and coordination of the oral speech mechanism. (Appended are checklists and rating scales, study tables, the language rating scales, and sources of tests used in the study). (DB)