One of the best tools used in identifying attention-deficit hyperactivity disorder (ADHD) could be less accurate when it comes to identifying the syndrome in a child who also suffers from an autism spectrum disorder (ASD).
According to the researchers, children with ASD could be mistakenly diagnosed with ADHD, because of the social impairments that are associated with both the disorders.
Identifying and understanding the key differences between the two is crucial for a good diagnosis as well as for the accuracy of the treatments' and services' effects on the children, according to the study.
A psychologist, part of the team who conducted the ADHD screening tool, established that the instrument needs to be adjusted in order to identify the correct disorder and to avoid, as much as possible, the misdiagnosis caused by the similarity of the two disorders' social symptoms. According to the psychologist, clinicians should provide a supplementary means of clinical interviews that would go along with the tool's screening process, to ensure the validity of the diagnosis.
"This is important because medications that work for ADHD may be less effective for a child on the autism spectrum," noted the study leader Benjamin E. Yerys, from the Center for Autism Research as part of the Children's Hospital of Philadelphia.
What makes the issue even more complicated is comorbidity. The fact that 30 percent, if not more, of the children suffering from ASD also have ADHD makes it more difficult to establish the boundaries of the symptoms associated with one disorders or another.
The scientists' solution is to be careful in not overestimating ADHD in children with ASD however descriptive and objectively useful the tool. The analyzed tool is the ADHD Rating Scale Fourth Edition, which asks the parents as well as the teachers of the children to rate 18 items about the child's behavior. Nine of these items concern inattention, and the other half hyperactivity and impulsivity.
The recommendations that come along with the study include modifying the rating scale, in order for it to better analyze the specific behaviors associated with each of the disorders, targeting the impact of the ASD symptoms on ADHD behaviors.
However, until a more specific scale will be available for large use in the diagnosis of these disorders, the specialized medical staff in the field will need to base their diagnosis on the follow-up interviews, examining the particular symptoms associated with the children's behavior and the possible suffering from one of the two syndromes.
According to the lead author of the study, it would be best if the clinicians who are in charge of diagnosing ASD also have relevant professional experience in dealing with ADHD symptoms in order to make a better difference between the two.