Present conceptualization of early childhood neurodevelopmental disabilities.

Neurodevelopmental disabilities are collectively a common problem in child health that frequently prompts neurologic assessment and intervention. They are a group of heterogeneous conditions that share a disturbance in the acquisition of basic developmental skills in a chronologically appropriate manner. Lacking uniform diagnostic means of ascertainment, their recognition depends on fulfilling present consensus opinion regarding the various subtypes now recognized. Distinctive subtypes of neurodevelopmental disabilities can be accurately diagnosed according to present consensus conceptualization. Dual diagnosis of neurodevelopmental disabilities in the same child is possible, given present opinion. It can be expected that these conceptualizations will be dynamic and guide ongoing research efforts that will elucidate basic mechanisms, effective therapeutic interventions, and evaluate outcomes.