In women aged 55-69 years at randomisation the relative rates of over-diagnosis of breast cancer ( 95 % confidence intervals ) were 1.32 ( 1.14 to 1.53 ) for period 1 , 0.92 ( 0.79 to 1.06 ) for period 2 , and 1.10 ( 0.99 to 1.22 ) at the end of follow-up .
