Outcome measures and data collection
anxiety, breast cancer
DISORDERS, BREAST CANCER
The primary outcome was the breast cancer screening rate in 2018. This was evaluated using a self‐administered questionnaire at the annual health checkup conducted in the workplace between January and March 2019. Participants also provided their history of breast cancer screening, history of breast cancer both personally and in close relatives, and pregnancy during the follow‐up period. Information about age, employment status, smoking status, body mass index, and score for the Japanese version of the Kessler Psychological Distress Scale (K6) were extracted from the health checkup data with the consent of the participants. The K6 is a self‐report questionnaire containing six questions. The optimal cutoff point was estimated to be 4/5 for mood and anxiety disorders in the Japanese general population.In the original study design, we had planned to follow the effects of the intervention for 2 years (up to 2019). However, following the positive response to the on‐site mammography in the intervention group in 2018, the employer's health insurance society decided to start providing mammography screening sequentially to all the stores in 2019. We therefore had to close the observations for this study at that point.