title: Predictive value of photoscreening and traditional screening of preschool children.
abstract: OBJECTIVE
  To compare the usefulness of traditional vision screening and photoscreening of 3- and 4-year-old children in the pediatrician's office.
  
  
  METHODS
  Following training of pediatricians and office staff, six pediatric clinics used both the MTI PhotoScreener (Medical Technology Industries, LLC, Riviera Beach, FL) and traditional acuity and stereopsis screening materials (HOTV charts/Random Dot E tests as recommended by established AAP-MCHB-PUPVS guidelines) during well-child exams. Clinics used one testing method for a 6-month period and switched to the other for the following 6 months, in a randomized manner. Referred children received a complete eye examination with cycloplegic refraction by local ophthalmologists or optometrists who forwarded the results to Vanderbilt Ophthalmology Outreach Center. Amblyogenic factors were defined using standardized published criteria.
  
  
  RESULTS
  Six hundred five children were screened with the photoscreener and 447 were screened with traditional techniques. Mean time for screening was less with the photoscreener: 2.5 versus 5.9 minutes ( P < 0.01). Untestable rates were similar (18% vs 10%, respectively P = NS), but higher with the photoscreener due to one clinic's 70% unreadable rate. Referral rates were also similar: 3.8% versus 4.5%. The positive predictive value (PPV) rate differed greatly. With follow-up results obtained from 56% of referred children, 73% of photoscreening referred children (8/11 examined) had amblyogenic factors confirmed on formal eye exams, whereas all children referred using traditional screening methods (10/10 examined) were normal.
  
  
  CONCLUSIONS
  Photoscreening is more time efficient than traditional screening and has a significantly higher PPV in 3- and 4-year-old children. This study was unable to validate traditional screening techniques in this preschool age group. If these results can be replicated, support for traditional vision screening must undergo intense scrutiny, and attention should be turned toward making photoscreening feasible for widespread implementation.
authors.affiliation: Vanderbilt University College of Arts and Science, Vanderbilt University School of Medicine, 8000 Medical Center East, Nashville, TN 37232-8808, USA.
authors.forename: April A
authors.initials: AA
authors.lastname: Salcido
authors.forename: Joel
authors.initials: J
authors.lastname: Bradley
authors.forename: Sean P
authors.initials: SP
authors.lastname: Donahue
mesh_terms: D000550:Amblyopia / Q000175:diagnosis* / Q000503:physiopathology; D002675:Child, Preschool; D018592:Cross-Over Studies; D003867:Depth Perception / Q000502:physiology; D005500:Follow-Up Studies; D006801:Humans; D019370:Observation; D010824:Physicians' Offices; D011237:Predictive Value of Tests; D011446:Prospective Studies; D015203:Reproducibility of Results; D015351:Vision Screening / Q000379:methods* / Q000592:standards; D014792:Visual Acuity / Q000502:physiology*