Pp. 21-26 (6)
Mohammed M.S. Jan
Developmental disorders are a group of early and chronic disorders affecting 5-10% of children.
Developmental delay is a subtype defined as significant delay in two or more of the following
developmental domains: motor (gross and fine), language (receptive an expressive), cognition, social and
adaptive activities. The estimated prevalence of global developmental delay is 1-3% of children younger
than 5 years. Developmental delay is a clinical presentation of a wide variety of congenital or acquired
etiologies. It results in significant learning deficits incompatable with the child’s chronological age.
Significant delay in a given developmental domain is defined as performance two standard deviations or
more below the mean for age. The term developmental delay is usually reserved for younger children (less
than 5 years of age), whereas the term mental retardation is usually applied to older children when IQ testing
is more reliable.
Neurological, Development, Disorders, Assessment, Delay, Regression, Evaluation, Mental
retardation, Genetic, Metabolic.
Professor & Consultant of Pediatric Neurology Department of Pediatrics Faculty of Medicine King Abdulaziz University Jeddah Kingdom of Saudi Arabia