Male male 4,278 human 4,110 Humans 4,101 female 3,813 Female 3,768 adult 2,739 Adult 2,211 middle aged 1,660 Middle Aged 1,654 Article 1,572 controlled study 1,538 young adult 1,343 Young Adult 1,320 adolescent 1,208 Adolescent 1,180 major clinical study 1,076 aged 1,075 Aged 1,003 physiology 922 child 867 psychology 848 procedures 786 Child 784 article 691 diagnostic imaging 618 pathology 469 questionnaire 457 clinical article 453 cross-sectional study 446