Child, Preschool Humans 124 controlled study human 124 preschool child 124 female 113 male 111 child 110 Male 100 Female 98 Child 86 Article 79 adult 60 infant 55 major clinical study 53 Infant 51 adolescent 49 Adolescent 48 Adult 46 young adult 34 Young Adult 32 article 31 psychology 30 clinical article 29 physiology 29 procedures 27 randomized controlled trial 27 child parent relation 25 middle aged 23 Middle Aged 22