Impact of stimulant medication on behaviour and executive functions in children with attention-deficit/hyperactivity disorder

Table 1 Participant demographic information at baseline (T1)

Variable	mean ± SD (n = 37)
Age	10.11 ± 1.27
Cognitive Tasks
WISC-IV-I VC SS	98.11 ± 11.69
WISC-IV-I MR SS	97.70 ± 12.89
BASC-2 Attention Problem T-Score	69.59 ± 6.31
BASC-2 Hyperactivity T-Score	71.73 ± 12.77
WJ-III Reading	90.49 ± 13.19
WJ-III Math	80.95 ± 13.86
WJ-III Written Language	87.03 ± 14.75
Biological Sex	n (%)
Female	16 (43.2)
Male	21 (56.8)

WISC-IV: Wechsler Intelligence Scale for Children, Fourth Edition; VC SS: Vocabulary Subtest Standard Score; MR SS: Matrix Reasoning Standard Score; BASC-2: Behaviour Assessment System for Children-Second Edition; WJ-III: Woodcock Johnson Test of Achievement, Third Edition.

Table 2 Behaviour Assessment System for Children-Second Edition parent symptom reports measured over the three-time points

Variable	BL T-score mean ± SD (n = 37)	BD T-score mean ± SD (n = 30)	BD-BL (P value)	FU T-score mean ± SD (n = 18)	FU-BD (P value)
Externalizing problems	68.95 ± 13.20	54.83 ± 8.42	P < 0.001	63.72 ± 10.26	P = 0.003
Internalizing problems	62.86 ± 15.34	52.53 ± 13.0	P < 0.001	60.89 ± 13.07	P = 0.063
Behaviour symptoms index	72.32 ± 10.20	57.13 ± 7.73	P < 0.001	68.06 ± 9.47	P < 0.001
Adaptive behaviours	33.95 ± 8.92	40.57 ± 9.22	P < 0.001	38.72 ± 8.79	P = 0.124

Mean scores on the Behaviour Assessment System for Children-Second Edition subscales; externalizing problems, internalizing problems, behavioural symptom index and adaptive skills, as rated by parents at three-time points: (1) Baseline; (2) Best-dose; and (3) Follow-up. BL: Baseline; BD: Best-dose; FU: Follow-up.

Table 3 Behaviour Rating Inventory of Executive Functioning-Second Edition parent symptom reports measured over the three-time points

Variable	BL T-score mean ± SD (n = 37)	BD T-score mean ± SD (n = 31)	BD-BL (P value)	FU T-score mean ± SD (n = 18)	FU-BD (P value)
Behavioural regulation index	72.43 ± 11.94	53.42 ± 8.78	P < 0.001	68.28 ± 13.23	P = 0.001
Metacognition index	74.76 ± 7.72	57.94 ± 8.48	P < 0.001	72.06 ± 9.51	P < 0.001

Mean scores on the BRIEF subscales; Behavioural Regulation Index and Metacognition Index as rated by parents at three-time points: (1) Baseline; (2) Best-dose; and (3) Follow-up. BL: Baseline; BD: Best-dose; FU: Follow-up.

Table 4 Neuropsychological Test Performance Scores measured over the three-time points

Variable	BL T-score mean ± SD (n = 37)	BD T-score mean ± SD (n = 33)	BD-BL (P value)	FU T-score mean ± SD (n = 18)	FU-BD (P value)
CPT omission errors (T-Score)	61.11 ± 15.76	52.88 ± 8.09	P = 0.001	49.34 ± 5.90	P = 0.10
CPT commission errors (T-Score)	53.59 ± 6.74	49.70 ± 11.75	P = 0.097	49.69 ± 10.17	P = 0.04
Digit Span Backwards	95.54 ± 11.04	99.19 ± 11.48	P = 0.059	96.94 ± 15.54	P = 0.055
Spatial Span Backwards	105.68 ± 12.42	108.23 ± 13.0	P = 0.332	108.06 ± 12.96	P = 0.782

Mean scores on the Continuous performance test commission errors (T-scores) and Wechsler Intelligence Scale for Children, Fourth Edition (standard score) at three-time points: (1) Baseline; (2) Best-dose; and (3) Follow-up. CPT: Continuous performance test; BL: Baseline; BD: Best-dose; FU: Follow-up.