Hazard ratios calculated per year with the control group as a reference.

aAll HRs were adjusted for age and sex and number of comorbidities.bAll, all controls were taken into account.cSelected, controls with the same characteristics as the patient subgroup were taken into account, e.g., selected malignancy are only controls with malignant disease.dHR could not be calculated, because there were no events.eIndividuals with malignancy excluded.fIdiopathic venous thrombosis were those without malignancy, surgery, hospital admission, injuries, plaster, oral contraceptive use and pregnancy and were not during puerperium.