And including date and place of birth,current and past addresses, civil status and date and death, immigration or disappearance. Using the Danish military’s company registration number, we identified all women born between 1929 and1968 who had ever been employed in any division of the Danish military between 1 April1964 and 31 December 1999, who were alive on 1 January 1990(in order to secure a relatively high proportion of cancer survivors) and were 75year old or younger at the time of completing the questionnaire (in order to reduce the likelihood of age-related memory problems) In total. 18 551 women fulfilled these criteria.
All 329 cases of primary breast cancer (ICD-7 170) in1990-2003 were documented from the files of the nationwide Danish Cancer Registry by use of the Central Person Registry number.