Background: The term high risk infant designates an infant who should be under close observation by experienced physicians and nurses and is born with biologic or environmental factors that carry an increased risk of developmental disability.
The aim of this study was early identification of high risk infants (18-24 months) by using chat questionnaire as a screening tool From outpatient pediatric clinics in Benha and Mansoura, 500 infants 250 (50%) were males and 250 (50%) were females, aged 18-24 months which appear normal were documented in a period of 9 months from 1st March 2004 to 30th Nov. 2004. Full medical and developmental history was taken, complete clinical and neurological examination and developmental screening using CHAT "check list for autism in toddlers" questionnaire were done.

As regard of CHAT questionnaire high risk infants were 10 cases (2%) of total studied cases, 6 cases of them (1.2%) are males and 4 cases (0.8%) are females, 490 cases (98%) of total studied cases were normal. 2 (33.3%) of male cases failed in one key item protodeclarative pointing (PDP), 3 cases (50%) failed in one key item pretend play (PP), 1 case (16.7%) failed in two key items PDP and PP. 1 (25%) of female cases failed in one key item PDP, 2 cases (50%) failed in one key item PP, 1case (25%) failed in two key times PDP and PP.

As raged to neurodevelopmental outcome of studied cases, motor, mental, speech and hearing impairment were detected in 30%, 50%, 70% and 30% respectively.
Conclusions: CHAT must use as primary screening tool for early detection of high risk infants as it is simple, highly specific and easily to use.