From: Overdiagnosis and overtreatment of breast cancer: Estimates of overdiagnosis from two trials of mammographic screening for breast cancer
Detection occasion
Number screened
Invasive cancers only
All cancers
First screen
18,197
55
70
First interval
7
9
Second screen
17,005
27
28
Second interval
14
Third screen
17,093
36
41
Third interval
21
23