Mammography screening and risk of XXXX : a population-based case-control study.

@entity1 @entity5 @entity0
BACKGROUND: Because the efficacy of mammography screening had been shown in randomized controlled trials, the focus has turned on its effectiveness within the daily practice. Using individual data of @entity1 invited to screening, we conducted a case-control study to assess the effectiveness of the Dutch population-based program of mammography screening. METHODS: Cases were @entity1 who died from @entity0 between 1995 and 2003 and were closely matched to five controls on year of birth, year of first invitation, and number of invitations before case's diagnosis. ORs and 95% confidence intervals (CI) for the association between attending either of three screening examinations prior to diagnosis and the risk of @entity0 were calculated using conditional logistic regression and corrected for self-selection bias. RESULTS: We included 755 cases and 3,739 matched controls. Among the cases, 29.8% was screen-detected, 34.3% interval-detected, and 35.9% never-screened. About 29.5% of the never-screened cases had stage IV @entity5 compared with 5.3% of the screen-detected and 15.1% of the interval-detected cases. The OR (95% CIs), all ages (49-75 years), was 0.51 (0.40-0.66) and for the age groups 50-69, 50-75, and 70-75 years were 0.61 (0.47-0.79), 0.52 (CI 0.41-0.67), and 0.16 (0.09-0.29), respectively. CONCLUSION: The study provides evidence for a beneficial effect of early detection by mammography screening in reducing the risk of @entity0 among @entity1 invited to and who attended the screening. IMPACT: This is the first case-control study that accurately accounts for equal screening opportunity for both cases and matched controls by number of invitations before case's diagnosis.
