human 42 Humans 40 intellectual impairment 37 male 37 female 35 Intellectual Disability 34 Article 31 adult 29 Female 22 Male 22 Adult 21 adolescent 21 controlled study 18 intellectual disability 18 child 16 major clinical study 16 Adolescent 15 middle aged 15 Child 14 Intellectual disability 13 young adult 11 clinical article 10 COVID-19 9 Middle Aged 9 Young Adult 9 cross-sectional study 9 Child, Preschool 8 Cross-Sectional Studies 8 preschool child 8 questionnaire 8