title: Variable size computer-aided detection prompts and mammography film reader decisions.
abstract: BACKGROUND
  The purpose of the present study was to investigate the effect of computer-aided detection (CAD) prompts on reader behaviour in a large sample of breast screening mammograms by analysing the relationship of the presence and size of prompts to the recall decision.
  
  
  METHODS
  Local research ethics committee approval was obtained; informed consent was not required. Mammograms were obtained from women attending routine mammography at two breast screening centres in 1996. Films, previously double read, were re-read by a different reader using CAD. The study material included 315 cancer cases comprising all screen-detected cancer cases, all subsequent interval cancers and 861 normal cases randomly selected from 10,267 cases. Ground truth data were used to assess the efficacy of CAD prompting. Associations between prompt attributes and tumour features or reader recall decisions were assessed by chi-squared tests.
  
  
  RESULTS
  There was a highly significant relationship between prompting and a decision to recall for cancer cases and for a random sample of normal cases (P < 0.001). Sixty-four per cent of all cases contained at least one CAD prompt. In cancer cases, larger prompts were more likely to be recalled (P = 0.02) for masses but there was no such association for calcifications (P = 0.9). In a random sample of 861 normal cases, larger prompts were more likely to be recalled (P = 0.02) for both mass and calcification prompts. Significant associations were observed with prompting and breast density (p = 0.009) for cancer cases but not for normal cases (P = 0.05).
  
  
  CONCLUSIONS
  For both normal cases and cancer cases, prompted mammograms were more likely to be recalled and the prompt size was also associated with a recall decision.
authors: Division of Applied Medicine, School of Medicine & Dentistry, University of Aberdeen, Lilian Sutton Building, Foresterhill, Aberdeen AB25 2ZD, UK. f.j.gilbert@abdn.ac.uk
authors: Fiona J
authors: FJ
authors: Gilbert
authors: Susan M
authors: SM
authors: Astley
authors: Caroline Rm
authors: CR
authors: Boggis
authors: Magnus A
authors: MA
authors: McGee
authors: Pamela M
authors: PM
authors: Griffiths
authors: Stephen W
authors: SW
authors: Duffy
authors: Olorunsola F
authors: OF
authors: Agbaje
authors: Maureen Gc
authors: MG
authors: Gillan
authors: Mary
authors: M
authors: Wilson
authors: Anil K
authors: AK
authors: Jain
authors: Nicola
authors: N
authors: Barr
authors: Ursula M
authors: UM
authors: Beetles
authors: Miriam A
authors: MA
authors: Griffiths
authors: Jill
authors: J
authors: Johnson
authors: Rita M
authors: RM
authors: Roberts
authors: Heather E
authors: HE
authors: Deans
authors: Karen A
authors: KA
authors: Duncan
authors: Geeta
authors: G
authors: Iyengar
mesh_terms: D000368:Aged; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000473:pathology; D003201:Computers; D003936:Diagnosis, Computer-Assisted / Q000379:methods*; D055088:Early Detection of Cancer; D005260:Female; D006801:Humans; D008327:Mammography / Q000379:methods*; D008403:Mass Screening / Q000379:methods; D008875:Middle Aged; D015588:Observer Variation; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods; D015203:Reproducibility of Results; D012107:Research Design; D016896:Treatment Outcome