The term “disorder” is used cautiously in this age group,
with some skepticism about its validity (Campbell, 2002).
Evidence for stability and prognostic significance of preschool
problems is not particularly strong, especially in the underthrees.
Comorbidity is very high, and there are also concerns
about distinguishing normal from abnormal behavior in this
period of rapid developmental change, and about labeling very
young children with disorders. However, there may also be disadvantages
of not defining disorders in young children, including
failure to recognize distress and provide appropriate help
(Carter, Briggs-Gowan, & Davis, 2004; Egger & Angold, 2006).
The latter is particularly important, given that there is a good
deal of evidence about effective interventions for this age group,
particularly for disruptive behavior problems.