Table 3.
Means, Standard Deviations, and Pairwise Comparisons for Attention-Deficit/Hyperactivity Disorder Entire Sample, Attention-Deficit/Hyperactivity Disorder Combined Subtype, Attention-Deficit/Hyperactivity Disorder Inattentive Subtype in Methylphenidate and Placebo Groups
| Pairwise comparisons to Placebo | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| MPH | Placebo | Cohen's d (p) | |||||||
| ADHD ALL (n = 45) | ADHD-C (n = 24) | ADHD-I (n = 21) | ADHD ALL (n = 44) | ADHD-C (n = 20) | ADHD-I (n = 24) | ADHD ALL | ADHD-C | ADHD-I | |
| Visual attention | |||||||||
| % Mean (SD) | 95.3 (4.4) | 94.8 (4.1) | 95.9 (4.7) | 91.2 (7.9) | 89.6 (9.1) | 92.6 (6.4) | 0.64 (0.001) | 0.76 (0.01) | 0.58 (0.049) |
| Range | 77–100 | 87–100 | 77–100 | 71–100 | 71–100 | 71–100 | |||
| Fidgeting | |||||||||
| % Mean (SD) | 49.1 (22.7) | 50.7 (21.8) | 47.4 (21.4) | 46.2 (23.4) | 46.1 (21.9) | 46.2 (24.5) | 0.13 (0.58) | 0.21 (0.61) | 0.05 (0.87) |
| Range | 1.5–89.0 | 8.1–89.0 | 1.5–83.8 | 7.3–98.9 | 10.1–89.9 | 7.3–98.9 | |||
| Accuracy | |||||||||
| Mean (SD) | 7.0 (1.2) | 6.9 (1.3) | 7.0 (1.0) | 6.4 (1.6) | 6.5 (1.5) | 6.4 (1.7) | 0.43 (0.002) | 0.29 (0.06) | 0.42 (0.009) |
| Range | 4–8 | 4–8 | 5–8 | 2–8 | 2–8 | 3–8 | |||
Accuracy measured in number of correct answers out of eight questions. Pairwise comparison p values derived from regression analysis in Mplus with medication status predicting the corresponding variable; therefore, discrepancies between p values are due to differences in Mplus estimating using maximum likelihood versus maximum likelihood with bootstrapping.
ADHD, attention-deficit/hyperactivity disorder; ADHD-C, ADHD Combined Subtype; ADHD-I, ADHD Inattentive Subtype; MPH, methylphenidate; SD, standard deviation.