Individual child data from the Preschool Screening Programs of 402 Minnesota school districts were analyzed for problem identification and referral rates, areas of problem identification and referral, sex differences in rates, and other factors. The results from over 45,000 children revealed large variability in rates among school districts, as well as differences as a function of the child's sex. Referral rates ranged from 0% to 72.7%. The most frequent problems identified and referrals made were in the areas of cognitive development (specifically speech/language) and hearing. Yet, variability among school districts also existed in areas where most problems are identified and referrals made. Results pointed out the need for further study of reasons for discrepancies in rates for males and females and for the wide variation found in both problem identification and referral rates. (Author/CL)