human 626 preschool child 622 Humans 579 Child, Preschool 549 child 523 female 509 male 500 Female 428 Male 428 Child 416 adolescent 228 Adolescent 212 adult 209 infant 206 Article 200 Infant 180 Adult 170 controlled study 158 major clinical study 143 psychology 128 young adult 123 Young Adult 114 article 109 physiology 101 child parent relation 88 middle aged 82 procedures 77 Middle Aged 76 clinical article 75 human experiment 72