Table 1.
Demographical and phenotypical characteristics of the study sample (n = 28)
| Frequency | |
| Sex | |
| Male | 14 |
| Female | 14 |
| Genotype | |
| Deletion | 15 |
| Non-deletion | 13 |
| Paternal uniparental disomy (UPD) | 7 |
| Imprinting center defect (ICD) | 1 |
| UBE3A mutation | 5 |
| Epilepsy | |
| Yes | 22 |
| Yes, active | 16 |
| Yes, controlled with anti-seizure medication | 6 |
| No | 6 |
| No, never | 4 |
| In remission (currently no anti-seizure medication) | 2 |
| Socio-economic statusa | |
| Low-level educationb | 1 |
| Middle-level educationc | 16 |
| High-level educationd | 11 |
| Comorbid psychiatric diagnoses | |
| No psychiatric diagnosis | 21 |
| Attention deficit hyperactivity disorder (ADHD) | 6 |
| Autism spectrum disorder (ASD) | 1 |
| Medication use | |
| Antiseizure medication | |
| Valproic acid | 13 |
| Clobazam | 10 |
| Levetiracetam | 6 |
| Topiramate | 3 |
| Diazepam, lamotrigin, or ethosuximide | 2 |
| Ethosuximide, gabapentine, clonazepam, lacosamide, brivaracetam, or rufinamide | 1 |
| Psychotropic medication | |
| Methylphenidate | 4 |
| Risperidone | 2 |
| Aripiprazol | 1 |
| No medication | 5 |
| Vision (as reported by parents) | |
| Normal vision | 9 |
| Farsightede | 9 |
| Strabismus | 8 |
| No stereovision | 5 |
| Nearsightede | 4 |
| Nystagmus | 2 |
| Walking abilities | |
| Walking independently | 18 |
| Walking with support | 7 |
| Wheelchair dependent | 3 |
| Mean (SD) | |
| Age | 11.04 (4.51) |
| CGI-S scoref | |
| Total | 4.68 (0.78) |
| Behavior | 4.00 (0.98) |
| Motor (fine/gross) | 4.68 (0.61)/4.29 (1.33) |
| Communication (expressive/receptive) | 4.93 (1.05)/3.50 (1.17) |
| Sleep | 3.46 (1.64) |
| PEDI-CAT scaled scores (N = 20)g | |
| Daily activities | 47.58 (4.17) |
| Mobility | 58.26 (5.28) |
| Social/cognitive | 53.89 (4.62) |
Abbreviations: CGI-S Clinical Global Impression of Severity Scale; PEDI-CAT Pediatric Evaluation of Disability Inventory Computer Adaptive Test
aDefined as highest education (average) of both parents
bLow-level education consisted of: no education or primary education only
cMiddle-level education consisted of: secondary education only or middle-level vocational education
dHigh-level education consisted of: high level vocational education, university education, or PhD education
eOnly one participant tolerated wearing glasses, while 12 others were supposed to wear glassed but did not tolerate them
fThe CGI was adapted to the AS population by the authors. A score of 1 represents normal development, 2 is slightly impaired, 3 is mildly impaired, 4 represents moderately impaired, 5 is markedly impaired, 6 is severely impaired, and 7 represents very severe impairments (among the most extremely impaired)
gScaled scores on the PEDI-CAT lay on a continuum of 20 (low function) to 80 (high function) and are not age-related. T-scores were not reported, as more than half of the population had a T-score lower than 10, under which no differentiation was possible