Response-time variability is related to parent ratings of inattention, hyperactivity, and executive function.
OBJECTIVE
Individuals with ADHD are often characterized as inconsistent across many contexts. ADHD is also associated with deficits in executive function. We examined the relationships between response time (RT) variability on five brief computer tasks to parents' ratings of ADHD-related features and executive function in a group of children with a broad range of ADHD symptoms from none to full diagnosis.


METHODS
We tested 98 children (mean age 9.9 ± 1.4 years; 66 boys) from community clinics on short tasks of executive control (TEC) and the Eriksen Flanker task, while a parent completed the Conners' Parent Rating Scale and Behavior Rating Inventory of Executive Function.


RESULTS
Variability for two of the TEC tasks explained significant proportions of the variance of all five ADHD-related Conners' subscales and several executive function subscales. By contrast, variability on the flanker task or mean RTs for any task were not associated with any rating scale.


CONCLUSIONS
The significant dimensional relationships observed between variability measures and parent ratings supported the utility of RT variability as an objective measure in ADHD and aspects of executive functioning that is superior to RT means or accuracy measures.
Gómez-Guerrero
Lorena
L
Servicio de Psiquiatría, Hospital Provincial de Pontevedra, Santiago de Compostela (La Coruña), Spain.
Martín
Cristina Domínguez
CD
Mairena
María Angeles
MA
Di Martino
Adriana
A
Wang
Jing
J
Mendelsohn
Alan L
AL
Dreyer
Benard P
BP
Isquith
Peter K
PK
Gioia
Gerard
G
Petkova
Eva
E
Castellanos
F Xavier
FX
D001288:Attention; D001289:Attention Deficit Disorder with Hyperactivity / Q000175:diagnosis* / Q000523:psychology; D002648:Child; D056344:Executive Function; D005260:Female; D006801:Humans; D006948:Hyperkinesis / Q000175:diagnosis* / Q000523:psychology; D008297:Male; D009483:Neuropsychological Tests; D010290:Parents; D010865:Pilot Projects; D011930:Reaction Time