Re: "Incidence and prevalence as measures of the frequency of birth defects".
D002140:California; D000013:Congenital Abnormalities / Q000453:epidemiology*; D006801:Humans; D007231:Infant, Newborn; D009436:Neural Tube Defects / Q000453:epidemiology; D009626:Terminology as Topic; D013997:Time Factors