Skip to main content

Table 1 Previous studies comparing executive functions in ASD vs. ADHD

From: Inhibition, flexibility, working memory and planning in autism spectrum disorders with and without comorbid ADHD-symptoms

  Ozonoff et al. 1999 Nyden et al. 1999 Geurts et al. 2004 Goldberg et al. 2005 Happé et al. 2006 Johnson et al. 2007
Sample (n) n = 93 n = 30 n = 136 n = 70 n = 94 n = 62
-Autism 40 10 41 17 32 21
-ADHD 24 10 54 21 30 23
-TD 29 10 41 32 32 18
ASD diagnosis (%)       
- HFA 40 (100) - 41 (100) 17 (100) 6 (19) 21 (100)
- AS - 10 (100) - - 26 (81) -
ADHD subtype (%) ? ?   ? ?  
- Combined s.    36 (67)    22
- Inattentive only s.    16 (29)    1
- Hyperactive/Impulsive s.    2 (4)    -
Inclusion of ADHD in ASD group ? ? Yes, no no no
    only inattentive subtype    
Age at testing (years) 12.1 10.0 9.3 11.2 10.1 11.2
Min-Max (6–18) (8–11) (6–13) (?) (8–12) (?)
IQ 103.4 95.6 103.1 107.6 101.8 101.2
Neuropsychological measures       
-Inhibition Stroop CWT Go-No-Go, RIT CT, CDT, TEA-Ch Stroop CWT Go-No-Go SART
-Working Memory - - S-OPT C SWM C SWM -
-Planning TOH - TOL C SOC C SOC -
-Flexibility WCST WCST WCST C ID/ED C ID/ED, -
      Verbal Fluency  
  1. Note: CDT = Circle Drawing Task; C ID/ED = CANTAB Intra-dimensional/extra-dimensional shift task; C SOC = CANTAB Stockings of Cambridge; C SWM = CANTAB Spatial WorkingMemory; CT = Change Task; RIT = Response Inhibition Task; SART = Sustained Attention to Response Task; S-OPT = Self-Ordered Pointing; Stroop CWT = Stroop Colour Word Test; TD = Typically developing group; TEA-Ch = Test of Everyday Attention for Children; TOH = Tower of Hanoi; TOL = Tower of London; WCST = Wisconsin Card Sorting Test;