Table 3.
Using extreme group membership to predict choice impulsivity in the MIDA task (boys only).
| Extreme group (top 5%) |
n (total) | IRR1 | SE2 | p | IRR 95% CI3 | Discrete change %points (rewards)4 |
|---|---|---|---|---|---|---|
| Post-reward delay condition | ||||||
| ADHD-IN 5 | 32(542) | 1.15 | 0.28 | .57 | (0.71, 1.84) | 1.94 (0.39) |
| ADHD-H/I 6 | 25(542) | 1.05 | 0.30 | .87 | (0.60, 1.84) | 0.64 (0.13) |
| ADHD-CO 7 | 19(542) | 1.37 | 0.35 | .21 | (0.83, 2.26) | 4.88 (0.98) |
| No post-reward delay condition | ||||||
| ADHD-IN 5 | 32(542) | 1.45 | 0.22 | .015 | (1.07, 1.97) | 12.33 (2.47) |
| ADHD-H/I 6 | 25(542) | 0.99 | 0.21 | .98 | (0.66, 1.51) | −0.14 (−0.03) |
| ADHD-CO 7 | 19(542) | 1.32 | 0.24 | .12 | (0.93, 1.88) | 8.95 (1.79) |
Note: Negative binomial regression models have been used to examine whether extreme group membership can predict choice impulsivity under each task condition.
1
Incidence rate ratio.
2
Robust standard error.
3
Confidence intervals.
4
Expected change in preference for smaller-immediate rewards with extreme group membership expressed in percentage points or raw rewards for a typical participant.
5
ADHD-Inattentive extreme group.
6
ADHD-Hyperactive/impulsive extreme group.
7
ADHD-Combined subtype extreme group. MIDA: Maudsley Index of Childhood Delay Aversion.