Estimating a woman's risk of having a pregnancy associated with Down's syndrome using her age and serum alpha-fetoprotein level.Cuckle, Wald, Thompson1987 MayTijdschriftartikel
Physical activity, exercise, and physical fitness: definitions and distinctions for health-related researchCaspersen, Powell, Christenson1985 Mar-AprTijdschriftartikel
Epidemiology of community-acquired respiratory tract infections in adults. Incidence, etiology, and impact.Garibaldi1985 Jun 28Tijdschriftartikel
The Tecumseh study of respiratory illness. X. Relation of acute infections to smoking, lung function and chronic symptoms.Monto, Ross1978 JanTijdschriftartikel
ASA physical status classifications: a study of consistency of ratings.Owens, Felts, Spitznagel1978 OctTijdschriftartikel