Developmental delay is the failure to acquire at a particular age, in a particular field of development (physical, emotional, cognitive or social), that particular level of ability which the majority of children of comparable age are expected to have acquired. The degree of delay varies from borderline to severe.

It can affect specific areas or all areas: Speech Gross motor Fine motor Cognitive Social Changes in quality of performance at any age: Exceptional docility or restlessness Appearing not to look or see Appearing not to hear or listen Poor eye-hand coordination Clumsiness Persistence of earlier patterns e.g. Still casting or mouthing by 18 months Parents are worried e.g. Children are slow or different from other children / Child is difficult for parents to understand or relate to

References
Manual of Developmental Paediatrics-The Hong Kong Society of child Neurology & Developmental Paediatrics1996 Child Development: Diagnosis and Assessment-Holt K S 1991

Useful link: www.aap.org/healthtopics/stages.cfm#inf