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.
Keywords: Neurological, Development, Disorders, Assessment, Delay, Regression, Evaluation, Mental retardation, Genetic, Metabolic.