Table 2.
Means (and standard deviations) for RTV for MZ and DZ twins, ADHD probands, siblings of probands and controls
| Population-based twin sample | ADHD and control sibling-pair sample | ||||
|---|---|---|---|---|---|
| MZ twins | DZ twins | ADHD probands | Siblings of probands | Controls | |
| Go/no-go task | |||||
| RTVslow | 218.31 (139.40) | 224.37 (153.59) | 312.79 (221.37) | 225.48 (169.37) | 143.54 (103.73) |
| RTVfast | 166.17 (59.45) | 157.78 (56.40) | 143.26 (67.81) | 187.49 (72.87) | 115.77 (57.77) |
| RTVincentive | 146.44 (75.90) | 143.73 (68.20) | 144.01 (91.98) | 188.85 (129.27) | 144.02 (55.01) |
| RTV-difslow-fast | 52.02 (134.84) | 67.25 (144.75) | 78.21 (141.26) | 121.45 (199.58) | 28.56 (98.36) |
| RTV-difslow-incentive | 71.55 (134.75) | 81.13 (151.76) | 55.95 (144.09) | 87.74 (184.19) | 25.63 (97.94) |
| Fast task | |||||
| RTVbaseline | 413.47 (281.78) | 412.03 (302.23) | 455.39 (343.55) | 357.82 (323.58) | 202.58 (178.50) |
| RTVFI | 213.55 (165.61) | 202.46 (129.54) | 204.70 (180.60) | 229.78 (156.82) | 122.99 (102.01) |
| RTV-difbaseline-FI | 199.87 (258.30) | 209.10 (274.25) | 150.38 (243.40) | 234.15 (287.44) | 79.52 (139.87) |
RTV, Reaction time variability; MZ, monozygotic; DZ, dizygotic; ADHD, attention deficit hyperactivity disorder; dif, difference score; FI, fast incentive.