<unk> s (SDD) was a classification of disorders characterized by delayed development in one<unk>  area or areas.<unk> s were contrasted to pervasive developmental disorders which were characterized by delays in the development of multiple basic functions including socialization and communication.
Specific developmental disorder
Neurodevelopmental disorder
Developmental disorder
Frontal lobe disorder
Multiple complex developmental disorder
Communication disorder
Motivational deficiency disorder
Developmental disability