Volume 6 Supplement 1

Symposium Mammographicum 2004

Open Access

Quality assurance of routinely collected data in the Computer Aided Detection Evaluation Trial

  • MA McGee1,
  • FJ Gilbert2,
  • SW Duffy1,
  • SM Astley3,
  • P Griffiths3 and
  • C Boggis3
Breast Cancer Research20046(Suppl 1):P77


Published: 14 July 2004

A study may only be feasible when routinely collected data (RCD) are used to identify participants. RCD from one centre in a retrospective study of computer-aided detection (CAD) in breast screening are considered. Double-read mammograms were re-read by a different reader using CAD (R2 ImageChecker®) and the cancer detection and recall rates were compared.

Subjects attended routine screening during 1996 and were aged 50 years or over. Among RCD subjects, 11,947 (92.5%) were eligible. From the study sample (n = 5037), a subsample of 650 (13%) subjects was examined.

Previous attendance was incorrect in all four subjects with earlier screening at a different centre. The reader was correctly recorded in all but one subject where it was missing on the paper copy. Whether a subject was recalled for further examination was correct for all subjects; however, single-reader recall, when recall was requested by only one radiologist, was incorrect in 22 (3%) cases; each was among the 53 (8%) recalls showing 42% were incorrect (95% confidence interval, 28–56%).

Single-reader recall was unreliable and previous attendance did not have sufficient detail to report the whether a screen was prevalent. Both were checked throughout the study. Issues raised when using RCD are discussed.

Authors’ Affiliations

Cancer Research UK
University of Aberdeen
University of Manchester


© BioMed Central 2004