Table 1.
Sample Characteristics at Study Entry
| Variable | Full Sample (N =248) | Placebo First (n=132) | Medication First (n=116) |
|---|---|---|---|
|
| |||
| Mean (SD) | Mean (SD) | Mean (SD) | |
| Age in years | 8.1 (1.8) | 8.1 (1.9) | 8.1 (1.8) |
| Female | 23 % | 21% | 24% |
| White | 88% | 85% | 92% |
| Black | 11 % | 15% | 6% |
| Hispanic | 85 % | 81% | 89% |
| Estimated full-scale IQ | 96.7 (12.7) | 96.9 (13.1) | 96.8 (12.8) |
| Medication Dosea | 20.8 (5.7) | 20.2 (4.3) | 21.8 (6.3) |
| Diagnosed with ADHD | 100% | 100% | 100% |
| Combined Subtype | 73.8 % | 74.4% | 73.0% |
| Predominantly Impulsive/Hyperactive Subtype | 8.1 % | 8.3% | 7.8% |
| Predominantly Inattentive Subtype | 18.1 % | 17.3% | 19.1% |
| Diagnosed with ODD | 63.5 % | 63.9% | 62.9% |
| Diagnosed with CD | 10.2 % | 9.2% | 11.3% |
| Number of ADHD impulsivity/hyperactivity symptoms endorsed on DBD-RS | 7.4 (2.2) | 7.42 (2.1) | 7.3 (2.1) |
| Number of ADHD inattention symptoms endorsed on DBD-RS | 8.4 (1.3) | 8.52(1.1) | 8.2 (1.4) |
| Number of ODD symptoms endorsed on DBD-RS | 4.7 (2.7) | 4.64 (2.6) | 4.7 (2.7) |
| Number of CD symptoms endorsed on DBD-RS | 1.0 (1.5) | 0.97 (1.5) | 1.1 (1.2) |
Note. IQ = intelligence quotient, ADHD = Attention Deficit Hyperactivity Disorder, ODD = Oppositional Defiant Disorder, CD = Conduct Disorder, DBD-RS = Disruptive Behavior Disorders Rating Scale.
a
daily medication dose in mg.
Values are means with standard deviations in parentheses, or proportions (%) for binary variables. Estimated full-scale IQ based on Wechsler Abbreviated Scale of Intelligence (Wechsler, 2011). Diagnoses were made at study entry as described in text. For symptom counts, symptom was counted as endorsed when either parent or teacher rated the symptom as occurring “pretty often” or “very often” on the DBD-RS (Pelham et al., 1992).