The probability value for each of the antiepileptic drugs (AEDs) studied being significantly associated with greater than 10% VFD using the Mann Whitney U test when comparing patients currently taking the AED to the control group
| AED | Mann Whitney U | Asymmetrical significance |
| VGB | 29.0 | 0.001 |
| CBZ | 8.0 | 0.520 |
| PHT | 38 | 0.93 |
| CLB | 16 | 0.175 |
| GBP | 45.5 | 0.648 |
| TPR | — | — |
| PHB | 5.0 | 0.304 |
| VPA | 19.0 | 0.219 |
| DZM | 9.0 | 0.107 |
| LTG | 48.5 | 0.435 |
VGB = vigabatrine, CBZ = carbamazepine, PHT = phenytoin, CLB = clobazam, GBP = gabapentin, TPR = topiramate, PHB = phenobarbitone, VPA = valproate, DZM = diazepam, LMG = lamotrigine.