title: Visual Function Assessment in Medical Imaging Research.
abstract: BACKGROUND
  Medical image perception research relies on visual data to study the diagnostic relationship between observers and medical images. A consistent method to assess visual function for participants in medical imaging research has not been developed and represents a significant gap in existing research.
  
  
  METHODS
  Three visual assessment factors appropriate to observer studies were identified: visual acuity, contrast sensitivity, and stereopsis. A test was designed for each, and 30 radiography observers (mean age 31.6 years) participated in each test.
  
  
  RESULTS
  Mean binocular visual acuity for distance was 20/14 for all observers. The difference between observers who did and did not use corrective lenses was not statistically significant (P = .12). All subjects had a normal value for near visual acuity and stereoacuity. Contrast sensitivity was better than population norms.
  
  
  CONCLUSIONS
  All observers had normal visual function and could participate in medical imaging visual analysis studies. Protocols of evaluation and populations norms are provided. Further studies are necessary to understand fully the relationship between visual performance on tests and diagnostic accuracy in practice.
authors.forename: Carla
authors.initials: C
authors.lastname: Lança
authors.forename: John D
authors.initials: JD
authors.lastname: Thompson
authors.forename: Luis
authors.initials: L
authors.lastname: Lança
authors.forename: Peter
authors.initials: P
authors.lastname: Hogg
mesh_terms: D000293:Adolescent; D000328:Adult; D035843:Biomedical Research / Q000379:methods*; D015350:Contrast Sensitivity / Q000502:physiology*; D003867:Depth Perception / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D011859:Radiography / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013647:Task Performance and Analysis; D014787:Vision Tests / Q000379:methods*; D014792:Visual Acuity / Q000502:physiology*; D055815:Young Adult