Sex research in Denmark--a comparison between 5 sexuological surveys.
D000022:Abortion, Spontaneous / Q000453:epidemiology; D000293:Adolescent; D000328:Adult; D000367:Age Factors; D003075:Coitus; D003273:Contraceptive Devices; D003718:Denmark; D005260:Female; D006801:Humans; D008297:Male; D011247:Pregnancy; D012725:Sexual Behavior