Study flowchart.
CERVICAL CANCER
Participants of this study are indicated in the gray cell.A total of 20,555 women who met the inclusion criteria were extracted from the database of Ichihara City Hall on December 22, 2020, and a pre-invitation letter was sent to them on February 1, 2021. Inclusion criteria were 1) women living in Ichihara City as of December 22, 2020; 2) women aged 30−59 years as of April 1, 2021; 3) the target population for cervical cancer screening provided by Ichihara City in 2021—that is, women whose age was an even number (the city set this eligibility requirement to offer cervical cancer screening once every two years to all women); and 4) women who had not received routine cervical cancer screening provided by Ichihara City for three or more years. The fourth inclusion criterion was established because we assumed that if implemented in Japan, the self-sampling HPV test would be used by routine screening non-responders as in other countries where the test has been implemented [