Demographic and temporal variables that characterize glioblastoma and glioma case and control study participantsa.

a. Case study participants were blood donors (1974–2007) to the Janus Serum Bank, Oslo, Norway, who were subsequently diagnosed with glioblastoma or other types of glioma. Control participants were individually matched to case participants on 2-year age interval, date of blood collection and sex.b. 95% confidence intervalc. Interquartile ranged. Not applicableDemographic and temporal variables that characterize glioblastoma and glioma case and control study participantsa.