Cognition in African children with attention-deficit hyperactivity disorder.

The aims of the study were: (1) to describe the performance of African children with symptoms of attention-deficit hyperactivity disorder on selected neuropsychologic tests and compare it with performance among peers of the same age without symptoms; (2) to explore through a factor analysis if the selected tests cover the same functions as known from studies in Europe and North America. A nested case-control approach was used to select the two groups of children. The tests were selected to measure aspects of executive functions, attention and memory functions as well as motor skills. A total of 185 schoolchildren (28 cases and 157 control subjects) aged 85 to 119 months old were included. The findings indicate only minor difference between children with symptoms of attention-deficit hyperactivity disorder and control subjects in most of the tasks. However, children with symptoms of attention-deficit hyperactivity disorder performed more poorly on tests of motor skills and had more violations of rules on the planning task. The factor analysis indicated a three-factor model, confirming that the selected tests could be used as measures of executive/motor functions, attention, and memory functions. Similar findings have been reported among children in Europe and North America.