[Mammographic over-screening: evaluation based on probabilistic linkage of records databases from the Breast Cancer Information System (SISMAMA)].

The Brazilian Ministry of Health recommends biennial mammographic screening for women aged between 50 and 69 years. Since screening is opportunistic in the country, the actual periodicity varies. This study sought to test a methodology for estimating over-screening due to excessive periodicity, defined as a smaller than recommended interval between exams, and its association with socio-demographic characteristics.