Testing gender differential item functioning for ordinal and binary scored parent rated ADHD symptoms

The study used the ordinal logistic regression method to examine gender differential item functioning (DIF) for ratings of the ADHD symptoms. This was examined for two different response scoring methods: ordinal and binary. Parents from the general community completed ratings for 742 and 733 primary school-aged girls and boys, respectively. Results indicate no gender DIF for all the ordinal scored inattention (IA) and hyperactivity/impulsivity (HI) symptoms, and all the binary scored IA symptoms. For the binary scored HI symptoms, there was DIF for one symptom, while DIF could not be computed for three symptoms. Overall, these findings suggest minimal gender DIF for the ADHD symptoms. The implications of the findings for the use of ADHD rating scales in clinical practice are discussed.