title: The law of halves.
authors.affiliation: Department of Social Medicine, Hadassah/Hebrew University Medical School, Jerusalem, Israel.
authors.forename: J
authors.initials: J
authors.lastname: Herman
mesh_terms: D002908:Chronic Disease / Q000453:epidemiology*; D004812:Epidemiologic Methods; D006801:Humans; D015995:Prevalence