female human male 5,933 Humans 5,259 adult 4,758 Female 4,383 Male 3,756 Article 2,917 controlled study 2,730 Adult 2,500 major clinical study 2,125 middle aged 2,040 Middle Aged 1,753 article 1,703 aged 1,602 young adult 1,571 adolescent 1,451 Young Adult 1,423 Adolescent 1,270 child 1,245 human experiment 1,191 clinical article 1,097 Aged 1,086 physiology 940 Child 916 psychology 915 procedures 912 questionnaire 735 diagnostic imaging 729 cross-sectional study 713