Response Variability in Children With Attention Deficit Hyperactivity Disorder (ADHD)

Phase 4

Completed

Conditions: Attention Deficit Hyperactivity Disorder

Interventions: Drug: placebo
Drug: Methylphenidate

Registration Number: NCT01238822

Lead Sponsor: Children's Hospital Medical Center, Cincinnati

Brief Summary: Children with Attention Deficit Hyperactivity Disorder (ADHD) have numerous areas of neuropsychological dysfunction including response inhibition, working memory, and attention. One neuropsychological outcome measure that consistently reveals between-group differences is response variability. However, until recently, differences in response variability have been reported as an ancillary finding or viewed as a nuisance in the analyses. The specific aims of the present study are to 1) Examine response variability in ADHD patients across neuropsychological tasks to understand the breadth of this specific deficit and to understand the relation between response variability and other neuropsychological outcome measures; 2) Assess whether response variability deficits are specific to either or both of the two most prevalent ADHD subtypes (i.e., Combined Type \[CT\] and Predominantly Inattentive Type \[PIT\]); 3) Determine whether response variability in ADHD patients is affected by either medication or a variety of environmental manipulations (e.g., reward); and 4) Understand the relationship between neuropsychological measures of response variability and naturalistic instances of variable performance. Forty-five children (aged 7-11) with ADHD-CT, 45 children with ADHD-PIT, and 45 normal controls will be recruited to examine response variability across a wide range of neuropsychological tests. Task parameters such as event rate, stimulus saliency, and the presence of operant reward will be modified on each test to determine the conditions under which response variability is manifested in children with ADHD. In addition, all children with ADHD will participate in a placebo-controlled, randomized medication trial with a psychostimulant medication to assess the effects of medication on response variability. Advanced analytic methods utilizing non-Gaussian distributions and fast Fourier Transforms of the reaction time data will be used to conduct detailed analyses of RT patterns across the ADHD and normal control groups. Further, the effects of task parametric manipulations and medication on response variability will be examined. Finally, relations between response variability on neuropsychological tests and response variability in a variety of real-world analog situations will be examined to evaluate the ecological validity of these deficits.

Detailed Description: Not available

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 96

Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Study & Design

Study Type: INTERVENTIONAL

Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Placebo	placebo	-
Low Dose Methylphenidate	Methylphenidate	Low dose: 18 mg methylphenidate
Medium Dose Methylphenidate	Methylphenidate	Medium Dosage: 36 mg if more than 50 kg and 27 mg if less than 50 kg
High Dose Methylphenidate	Methylphenidate	54 mg if more than 50 kg and 36 mg if less than 50 kg

Primary Outcome Measures

Name	Time	Method
Attention Deficit / Hyperactivity Disorder Total Sum Score of All 18 ADHD Symptom Items	end of first week, end of second week, end of third week, end of fourth week. Total of 4 weeks.	Parent and teacher Vanderbilt ADHD Rating Scales - Attention Deficit / Hyperactivity Disorder Total sum score of all 18 ADHD symptom items - range equals 0-54 O - No ADHD symptoms 54 - Highest ADHD symptoms

Secondary Outcome Measures