The effect of false positive breast screening examinations on subsequent attendance: retrospective cohort study

Abstract

Objectives To investigate the effect of false positive breast screening examination results on subsequent attendance in the UK National Health Service Breast Screening Programme. Methods 253,017 previously screened women who were invited for rescreening were studied. Attendance rates of women who had received a normal result at the last (index) screen were compared with those of women who had received a false positive result. The effects of age, type of index screening examination ( prevalent or incident) and tissue sampling at assessment were investigated.Results Women who had a false positive prevalent index screening examination were significantly more likely to reattend than those who had a normal prevalent index screening examination (87.7% vs. 86.0%). There was no significant difference in reattendance rates between women who had a false positive incident index screening examination and those with a normal incident index screening examination. However, women who underwent needle sampling or open biopsy following false positive incident index screening examinations were 12% and 60% less likely to reattend, respectively, than women whose index screening examinations were normal ( p , 0.001), although there was variation between centres. Increasing age significantly reduced the likelihood of reattendance. The overall reattendance of women who had been screened only once was six percentage points lower than that of women who had been screened more than once. Conclusions The findings suggest that most women who undergo the breast screening assessment process retain confidence in breast screening. Needle sampling and open biopsy should be used judiciously in the assessment of screen-detected abnormalities in view of the reduced reattendance that results from their use after incident screening examinations.

Controversies in Screening Mammography

“…In their retrospective cohort study of 253,017 women, they found that women with a false-positive mammogram were more likely to return for subsequent screening than those who had normal screening, 87.7% versus 86.0%. 52 …”

The impact of false positive breast cancer screening mammograms on screening retention: A retrospective population cohort study in Alberta, Canada

“…This is of concern as more frequent screening results in higher cumulative false positive findings, 26 which in turn increases the risk of invasive procedures and, based on our study and others, 6 lowers screening retention. In addition, modeling studies show that biennial screening does not lead to higher prevalence of latestage breast cancer than annual screening.…”

“…10 A recent study in the United Kingdom showed that while the retention rate was not affected by false positives, it was reduced in women who underwent biopsies. 6 Two studies in Canada, both published over a decade ago, found that false positive screening results reduced the likelihood of screening retention. 11,12 There are important differences in the organization and delivery of screening programs and in the characteristics of the populations screened across different countries.…”

“…4,5 The latter two have been shown to be associated with depression and long-term anxiety in women and possibly reduce the likelihood of future screening. 6,7 False positives account for about 9% of all screening mammograms and make up approximately 93% of abnormal calls in Canada and the US. 8,9 It is therefore important to understand the magnitude of the impact of false positives on screening retention in order to mitigate it.…”

On assessing the effect of breast cancer screening schemes

“…5 Biennial screening from age 50 to 74 years is projected to cause approximately one-fifth of the radiationinduced breast cancer cases caused by annual screening beginning at age 40 years. In one study, pathologists disagreed about the diagnosis of invasive breast cancer in 11% of cases (95% CI, [8][9][10][11][12][13][14][15][16] and about the diagnosis of ductal carcinoma in situ in 21% of cases (95% CI, 19-24). 5 The model estimates that annual screening of 100,000 women from age 40 to 74 years will avert 928 breast cancer deaths.…”