Definition

A developmental delay is any significant lag in a child's physical, cognitive, behavioral, emotional, or social development, in comparison with norms.

Description

Developmental delay refers to when a child's development lags behind established normal ranges for his or her age. Sometimes the term is used for mental retardation, which is not a delay in development but rather a permanent limitation. If most children crawl by eight months of age and walk by the middle of the second year, then a child five or six months behind schedule in reaching these milestones may be classified as developmentally delayed regarding mobility.

At least 8 percent of all children from birth to six years have...