A standardized medical examination of four to five year old children was introduced into Victorian preschools in 1977. This combined a neurodevelopmental screening with a physical examination. In a study to verify the effectiveness of this examination, a random sample of 512 children from inner urban and disadvantaged outer urban preschools was examined and compared with a group of 500 children from preschools in more advantaged areas. Of these 1012 children, 264 (26%) required referral for one or more previously unrecognized disabilities. The number of children referred for intervention or therapy from the disadvantaged group was 176 (34%) compared with 88 children (17.6%) from the more advantaged group. A standardized examination of the preschool child is desirable, so that consistently comparable results can be obtained and epidemiological trends can be more readily identified.