title: Field testing of the plusoptiX S04 photoscreener.
abstract: OBJECTIVE
  To evaluate the diagnostic accuracy of the plusoptiX S04 digital photoscreener in a school screening program.
  
  
  METHODS
  Between 2006 and 2007, 1343 information pamphlets/consent forms were sent to all junior kindergarten students in a local school district. Assistants from a local public health unit photographed 307 children. Of these, 271 children received an independent ophthalmic examination by a physician. Photographic results were compared with the those of the ophthalmic examination. Amblyopia risk factors were defined as anisometropia >1 D (sphere or cylinder), astigmatism >1.25 D, myopia >3 D, hyperopia >3.5 D, any manifest strabismus, and any media opacity.
  
  
  RESULTS
  Photographic and examination results agreed in 94% of cases. Sensitivity in detecting amblyopia risk factors was 83%; specificity was 95%. The positive and negative predictive values were 73% and 97%, respectively. The untestable/unusable rate was 1%.
  
  
  CONCLUSIONS
  These results compare favorably with a previously reported (but no longer available) digital photoscreening camera and are superior to results obtained with other off-axis photoscreening devices that require human interpretation. On the basis of these results, in a real-world screening program, the camera would falsely refer 4% of those screened and would fail to correctly refer 2%. The accuracy of the plusoptiX S04 camera in detecting amblyopia risk factors appears sufficiently high to consider its further deployment in a widespread school screening program.
authors.affiliation: Queen's University, Kingston, Ontario, Canada.
authors.forename: Brian W
authors.initials: BW
authors.lastname: Arthur
authors.forename: Rehan
authors.initials: R
authors.lastname: Riyaz
authors.forename: Sylvia
authors.initials: S
authors.lastname: Rodriguez
authors.forename: Jonathan
authors.initials: J
authors.lastname: Wong
mesh_terms: D000550:Amblyopia / Q000175:diagnosis* / Q000453:epidemiology; D015858:Anisometropia / Q000175:diagnosis / Q000453:epidemiology; D001251:Astigmatism / Q000175:diagnosis / Q000453:epidemiology; D002675:Child, Preschool; D006801:Humans; D006956:Hyperopia / Q000175:diagnosis / Q000453:epidemiology; D009216:Myopia / Q000175:diagnosis / Q000453:epidemiology; D010781:Photography; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012015:Reference Standards; D015203:Reproducibility of Results; D012307:Risk Factors; D012680:Sensitivity and Specificity; D013285:Strabismus / Q000175:diagnosis / Q000453:epidemiology; D015351:Vision Screening / Q000295:instrumentation* / Q000592:standards*