GARCIA-ROSALES, A., Vitoratou, S., Banaschewski, T., Asherson, P., Buitelaar, J. K., Oades, R. D., Rothenberger, A., Steinhausen, H-C., Faraone, S. V., Chen, W.,

Are all the 18 DSM.IV and DSM.5 criteria equally useful for diagnosing ADHD and predicting comorbid conduct problems?

European Child and Adolescent Psychiatry, 24, 1325-1337.(request a copy)

Introduction: In view of the ICD-11 revision, we evaluate whether the 18 DSM-IV diagnostic items retained by DSM-5 could be further improved (i) in predicting ADHD 'caseness' & 'impairment' and (ii) discriminating ADHD without Conduct Disorder (ADHD - CD) cases from ADHD with Conduct Disorder (ADHD + CD) cases.

Method: In a multi-centre study sample consisting of 1497 ADHD probands & 291 unaffected subjects, 18 diagnostic items were examined for redundancy; then each item was evaluated for association with caseness, impairment and CD status using Classical Test Theory, Item-Response Theory and logistic regression methods.

Results:

1/ All 18 DSM-IV items contributed significantly & independently to the clinical diagnosis of ADHD.

2/ Not all the DSM-IV items carried equal weighting. "Often loses things", "forgetfulness" and "difficulty sustaining attention" mark severity for Inattentiveness (IA) items and "often unduly noisy", "exhibits a persistent pattern of restlessness", "leaves seat in class" and "often blurts out answers" for Hyperactivity/Impulsivity (HI) items.

3/ "Easily distracted", "inattentive to careless mistakes", "often interrupts" and "often fidgets" are associated with milder presentations

4/ In the Inattentive (IA) domain, "distracted" yields most information in the low-severity range of the latent trait, "careless" in the mid-severity range and "loses" in the high-severity range.

5/ In the hyperactive-impulsive (HI) domains, "interrupts" yields most information in the low-severity range and "motor" in the high-severity range.

6/ All 18 items predicted impairment.

7/ Specific ADHD items are associated with ADHD + CD status.

Discussion:

a) The DSM-IV diagnostic items were valid and not redundant

b) However, some carried more-weight than others

c) All items were associated with impairment