Early Childhood Education

Developmental Delay


While all children grow and change at their own rate, some children can experience delays in their development. Developmental delay is a descriptive term used in reference to an assessment of delay in infants and young children in one or more of the following areas: cognitive development, physical development (which includes fine motor and gross motor), communication development, social development, emotional development, or adaptive development. If a child is slightly or only temporarily lagging behind, that is not considered developmental delay. Developmental delay is recognized by the failure to meet age-appropriate expectations that are based on the typical sequence of child development.

Significant delays in acquisition of developmental milestones in one or more developmental areas would indicate developmental delay and eligibility for early childhood special education. Parents usually seek an evaluation for developmental delay once their child fails to meet specific developmental milestones. In early infancy, indicators of developmental delay include a lack of responsiveness, unusual muscle tone or posture, and feeding difficulties. After six months of age, motor delay is the most common complaint. Language and behavior problems are common concerns after eighteen months. Although physical and cognitive delays may occur together, one is not necessarily a sign of the other. In addition, developmental milestones achieved and then lost should also be investigated, as the loss of function could be sign of a degenerative neurological condition.

Each state is responsible for developing more specific definitions of developmental delay, as well as criteria for determining eligibility for services for young children and their families residing in that state. Individual states have defined developmental delay variously as exhibiting a certain percentage of delay in one or more developmental areas, lower functioning than expected for chronological age, informed clinical judgment, atypical development, or a combination of some or all of these definitions. Those criteria measured by standardized assessment instruments are expressed in standard deviations from the mean; percent delay; number of months delay; or a developmental quotient (DQ), similar to an intelligence quotient (IQ) score. Criteria that are less quantifiable include atypical development as judged by a trained clinical professional or a multidisciplinary team.

Children who have a high probability of experiencing developmental delays include those who could be considered at established risk, biological risk, and/or environmental risk. Children who have genetic conditions or other medically diagnosed disorders that gives them a high probability of later delays in development have an established risk. Conditions such as Down syndrome, muscular dystrophy, and hearing impairment are examples. Children in this category are eligible for special education services by virtue of their diagnosis, regardless of whether a measurable delay is present. Children considered at biological risk have biological histories or conditions that make them more likely to develop a delay than children without the condition. Birth trauma, prematurity, failure to thrive, or complications during pregnancy all put a child at biological risk. The classification of young children who are at environmental risk is intended for children whose environments do not provide for their basic needs, including adequate nutrition, clothing, and shelter to provide psychological and emotional security. Children living in inadequate environments may experience mental, emotional, and/or physical disabilities. Developmental delays and disabilities are most likely to occur when a child is exposed to multiple risk factors, which may be biological, environmental, or both.

The Individuals with Disabilities Education Act (IDEA) permits states and schools to use a noncategorical classification such as developmental delay for children ages 3 through 9. This term is used when a definitive diagnosis has not been made, but a child shows persistent delay across domains. In identifying infants and toddlers, a general term such as developmental delay must be used. This law requires that young children with developmental delays receive early intervention services as needed. In addition, Part C under IDEA permits, but does not require, states to provide early intervention services for infants and toddlers who are at risk of developmental delays or disabilities but do not display any actual delays or activity limitations. See also Development, Emotional; Development, Social.

Further Readings: Division for Early Childhood (DEC). February 2005. Available online at http://www.dec-sped.org; Lerner, Janet W., Lowenthal, Barbara, and Egan, Rosemary W. (2003). Preschool children with special needs. Boston: Pearson Education.

Sharon Judge