The trained telephone interviewers

The trained telephone interviewers were blinded to case or control status. For the women who did not answer the questionnaire and could not be contacted by telephone, the postal address and vital status were retrieved from the Central Person Register and a repeat postal invitation was sent. Overall, the questionnaire was completed in 141 (67%) cases and by 551 (61%) controls.
Night shift work was defined as working for at least 1 year during hours beginning after 17:00 and ending before 9:00. Not including overtime. This includes exposure to artificial light after midnight, when melatonin normally peaks in healthy people.
In this definition, permanent and rotating night shifts were assessed as one entity. We recorded first calendar year, total duration (1-2,3-5,6-9,10-15,15-19,20-29 and ≥30 year) and the average number (continuous) of such shifts per week in periods with night work. We did not separate out night shift work with the military from that outside. Cumulative exposure (ie, lifetime number of night shifts) was calculated as the average number of night shifts per week multiplied by the midpoint of the upper and lower boundaries of the duration of midpoint of shift work categorized in the questionnaire. Tertiles for exposed controls were used as cut-off points in the analyses.
Occupational exposure to radar, equipment in the military, including potential exposure to electromagnetic fields (EMF), which have been the subject of intense debate in the media as a cause of cancer, was used as an indicator of recall bias. A woman was classified as exposed to EMF if she gave a positive answer to at least one of two questions: “ Have you operated radar equipment ?” and “Have you used surveillance equipment in operating theatres?"

ผลลัพธ์ (อังกฤษ) 2:

The trained telephone interviewers were blinded to case or control status. For the women who did not answer the questionnaire and could not be contacted by telephone, the postal address and vital status were retrieved from the Central Person Register and a repeat postal invitation was sent. Overall, the questionnaire was completed in 141 (67%) Cases and by 551 (61%) Controls.
Night Shift Work was defined as working for at Least 1 year after five p.m. during hours Beginning and Ending before 9 o'clock. Not including overtime. This includes exposure to artificial Light after Midnight, when melatonin Peaks in Healthy people normally.
In this Definition, and Permanent Rotating Night shifts were Assessed as one Entity. We recorded first calendar year, total duration (1-2,3-5,6-9,10-15,15-19,20-29 and ≥30 year) and the average number (continuous) of such shifts per week in. periods with night work. We did not separate out night shift work with the military from that outside. Cumulative exposure (ie, lifetime number of night shifts) was calculated as the average number of night shifts per week multiplied by the midpoint of the upper and lower boundaries of the duration of midpoint of shift work categorized in the questionnaire. Tertiles for exposed Controls were used as Cut-off points in the analyzes.
Occupational exposure to Radar, Equipment in the Military, including potential exposure to electromagnetic Fields (EMF), which have been the subject of Intense debate in the Media as a Cause of. cancer, was used as an indicator of recall bias. A woman was classified as exposed to EMF if she gave a positive answer to at least one of two questions: "Have you operated radar equipment?" And "Have you used surveillance equipment in operating theatres?".