title: Relating influenza epidemics to childhood leukemia in tumor registries without a defined population base: a critique with suggestions for improved methods.
mesh_terms: D000293:Adolescent; D002140:California; D002648:Child; D002675:Child, Preschool; D004196:Disease Outbreaks; D004812:Epidemiologic Methods; D005006:Ethnicity; D005260:Female; D005865:Gestational Age; D006801:Humans; D007223:Infant; D007251:Influenza, Human / Q000150:complications* / Q000453:epidemiology; D007938:Leukemia / Q000209:etiology*; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000453:epidemiology; D012042:Registries; D012306:Risk; D012621:Seasons