Table 4.

Impact of disease attributes and cancer treatment on the relative effect of exposure to breast screening according to time since last breast screen

Time since last breast screenAdjustmentOR (95% CI, P value)
Never screened_1.00 (—)
Screened 3–36 monthsDeprivation + attendance at cervical screeninga0.60 (0.42–0.85, 0.004)
Screened >60 monthsDeprivation + attendance at cervical screening0.68 (0.47–0.98, 0.04)
Screened 36–60 monthsDeprivation + attendance at cervical screening0.63 (0.37–1.05, 0.07)
Screened 24–36 monthsDeprivation + attendance at cervical screening0.61 (0.39–0.93, 0.02)
Screened 3–24 monthsDeprivation + attendance at cervical screening0.59 (0.39–0.89, 0.01)
Screened ≤3 monthsaDeprivation + attendance at cervical screening0.26 (0.18–0.37, <0.001)
Screened 3–36 monthsDeprivation + attendance at cervical screening + tumor characteristics0.73 (0.50–1.08, 0.1)
Screened >60 monthsDeprivation + attendance at cervical screening + tumor characteristics0.82 (0.55–1.25, 0.4)
Screened 36–60 monthsDeprivation + attendance at cervical screening + tumor characteristics0.85 (0.48–1.50, 0.6)
Screened 24–36 monthsDeprivation + attendance at cervical screening + tumor characteristics0.75 (0.47–1.21, 0.2)
Screened 3–24 monthsDeprivation + attendance at cervical screening + tumor characteristics0.72 (0.46–1.13, 0.2)
Screened ≤3 monthsDeprivation + attendance at cervical screening + tumor characteristics0.59 (0.39–0.88, 0.01)
Screened 3–36 monthsDeprivation + attendance at cervical screening + tumor characteristics + treatment0.74 (0.50–1.10, 0.1)
Screened >60 monthsDeprivation + attendance at cervical screening + tumor characteristics + treatment0.81 (0.53–1.24, 0.3)
Screened 36–60 monthsDeprivation + attendance at cervical screening + tumor characteristics + Treatment0.90 (0.50–1.24, 0.7)
Screened 24–36 monthsDeprivation + attendance at cervical screening + tumor characteristics + treatment0.76 (0.47–1.24, 0.3)
Screened 3–24 monthsDeprivation + attendance at cervical screening + tumor characteristics + treatment0.73 (0.46–1.16, 0.2)
Screened ≤3 monthsDeprivation + attendance at cervical screening + tumor characteristics + treatment0.64 (0.42–0.97, 0.03)

NOTE: Treatment variables included surgery, radiotherapy, chemotherapy, and endocrine therapy; tumor characteristics included size, lymph node status, stage, histologic grade, histologic type, and laterality.

  • aSelf-selection adjustment using deprivation quintile and attendance at cervical screening. See categorization in Table 1.