title: Age-based refinement of referral criteria for photoscreening.
abstract: OBJECTIVE
  To evaluate examination results from preschool children referred from photoscreening, and to adjust referral criteria for suspected astigmatism.
  
  
  METHODS
  Cross-sectional study and noncomparative case series.
  
  
  METHODS
  Thirty-one thousand fifty-three preschool children.
  
  
  METHODS
  Analysis of (1) referral rate and unreadable photograph rate for all children screened, (2) examination results and treatment plan for all children referred for suspected astigmatism, and (3) examination results and treatment for all referred children aged less than 1 year.
  
  
  METHODS
  Referral rate, unreadable photograph rate, predictive value positive, treatment plan.
  
  
  RESULTS
  The referral rate dropped from 7.8% for children 6 to 11 months to 5.3% for all other ages. The unreadable photograph rate declined exponentially from 12.1% for children aged 6 to 11 months to 1.1% for children aged 4 years. The predictive value positive of a photoscreen referral for all children in the 6- to 11-month age group was 30%, and only 12 of the 94 referred children were treated. The predictive value positive for children less than 1 year of age referred with suspected astigmatism was even lower (25%), and only one child in this age group was treated. The predictive value positive increased with age, and a higher percentage of older children were treated. For children at least 3 years old referred for suspected astigmatism, the predictive value positive was 67% when the examination was performed by a pediatric ophthalmologist. Strabismus, anisometropia, and high hypermetropia were diagnosed in such patients age 2 and older but never in younger children.
  
  
  CONCLUSIONS
  Children less than 1 year of age have a much lower pass rate from photoscreening than do older children because of a higher referral rate and higher unreadable rate in this age group. When these children are examined, significant pathosis is usually absent, and intervention is rarely initiated. Most children age 2 and older who are referred for suspected astigmatism have a high likelihood of significant pathosis. It is probably unnecessary to examine children less than age 2 when their photoscreening suggests only astigmatism; conversely, referrals should still be provided for these children when their screening suggests other potentially amblyogenic factors.
authors.affiliation: Department of Ophthalmology and Visual Sciences, Vanderbilt University School of Medicine, 8000 Medical Center East, Nashville, TN 37232-8808, USA.
authors.forename: S P
authors.initials: SP
authors.lastname: Donahue
authors.forename: T M
authors.initials: TM
authors.lastname: Johnson
mesh_terms: D000367:Age Factors; D000550:Amblyopia / Q000175:diagnosis*; D001251:Astigmatism / Q000175:diagnosis*; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D005189:False Positive Reactions; D006801:Humans; D007223:Infant; D010781:Photography / Q000379:methods*; D011237:Predictive Value of Tests; D012017:Referral and Consultation / Q000592:standards; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D015351:Vision Screening / Q000379:methods*