Determinants of false positive recall rates in an Australian mammographic screening programme

We assessed the clinical and service related determinants of false positive recall using a case–control study of women who attended BreastScreen Victoria between 1994 and 1999. Cases were randomly selected from all women who were recalled for assessment but did not have cancer (false positives), and controls were selected from women who had a negative assessment and did not have cancer. Separate analyses were conducted for first (n = 12,667) and subsequent rounds (n = 17,461).

To identify reader characteristics associated with false positive recall we conducted generalised linear modeling of all women who attended between 1994 and 1999.

In the case–control study year of screen, strong family history and age at screening were important predictors of false positive recall at first round. At subsequent rounds, age, time since introduction of Kodak MIN-R-2000 film, strong family history of breast cancer, hormone replacement therapy use, recall at previous screen, previous screen at more than 27 months and screening round were significant predictors.

In the analysis of reader characteristics, false positive recall rates were found to increase with increasing number of screening reads per reader over the preceding 12-month period, but the number of assessment clinics each reader had attended heavily modified this finding.