An examination of the relationship between movement problems and four common developmental disorders.

It has been well recognized since the days of "minimal brain dysfunction" (Clements, 1966) that various developmental disorders have a shared aetiology. Poor motor coordination has been implicated as one of the factors in these relationships. This study examines the different patterns in symptomatology of five developmental disorders, namely developmental coordination disorder (DCD), attention-deficit/hyperactivity disorder (ADHD), reading disorder (RD), oppositional defiant disorder (ODD), and conduct disorder (CD) in order to build on the genetic work from Martin, Levy, Piek, and Hay (2006) and Martin, Piek, and Hay (2006) examining the overlap of these disorders. Latent class analysis was used on questionnaire data from 1304 families from the Australian twin ADHD project (ATAP) to examine the patterns of comorbidity of the five disorders. We confirmed and added detail to the shared symptoms between DCD, ADHD, RD, and ODD, but found no links between CD symptoms and any other disorders. Despite the close link previously identified with ODD and CD, this finding suggests a different aetiology for CD.

The relationship between fine and gross motor ability, self-perceptions and self-worth in children and adolescents.

The present study examined the impact of fine and gross motor ability on self-perceptions of male and female children and adolescents. Participants were compared across age group, sex, and level of motor ability. When intercorrelations between self-perceptions were taken into account, the level of movement ability was found to impact upon perceived athletic competence and scholastic competence. When movement was considered in terms of fine and gross motor ability, it was found that those with higher perceived scholastic competence were in the younger group and had better fine motor skills. Furthermore, those with greater perceived athletic competence were also in the younger group, were predominantly male and had better gross motor skills. The types of self-perceptions that influenced self-worth were dependent on the level of motor ability of the participants and varied according to their sex. The implications of these findings are discussed with reference to the necessity to assess specific types of motor deficit when tailoring intervention strategies for children with motor disorders, particularly within the academic setting.