Table 2.

Descriptive statistics for the neurocognitive variables for the participants ≥6 years of age

MeasureMeanSDConfidence Interval Range (5th Percentile; 95th Percentile)% >1 SD below Meana
WASI
    verbal IQ98.017.070; 12321
        vocabulary47.612.026; 6627
        similarities48.711.927; 6624
    performance IQ95.416.370; 12027
        block design46.311.329; 6433
        matrix reasoning47.611.226; 6326
    full-scale IQ96.416.568; 12125
WIAT-II-A
    basic reading96.517.166; 12026
    spelling96.216.868; 12226
    numerical operations93.720.260; 12633
    total achievement95.217.867; 12631
CPT-II
    omissionsb51.713.542; 7915
    commissions51.711.032; 6623
    variability50.111.035; 6822
    reaction time48.211.931; 7017
BRIEF-P
    behavioral regulation indexb53.511.139; 7428
        inhibition52.911.340; 7527
        shift of set53.010.938; 7428
        emotional control53.211.138; 7529
    metacognition index55.911.539; 7635
        initiation55.111.238; 7630
        working memory56.812.240; 7940
        planning55.711.838; 7736
        organization53.49.737; 6927
        monitoring54.011.536; 7330
    global executive composite55.211.639; 7633
  • Wechsler Abbreviated Scales of Intelligence (WASI) intelligence quotients (IQ) and Wechsler Individual Achievement Test-II-Abbreviated (WIAT-II-A) scores are reported as standard scores with means of 100 and a standard deviation of 15, and WASI subtests have a mean of 50 and a standard deviation of 10. For these tasks, higher scores reflect more intact abilities. Conners' Continuous Performance Test-II (CPT-II) and Behavior Rating Inventory of Executive Functions (BRIEF) scores are reported as standard scores with a mean of 50 and a standard deviation of 10, and higher scores reflect more impaired abilities.

  • a ≤1 SD below mean for WASI and WIAT-II-A variables and ≥1 SD above mean for CPT-II and Behavior Rating Inventory of Executive Functions-Parent (BRIEF-P) variables.

  • b Log transformations were required.