title: Forensic application of optical correction.
abstract: BACKGROUND
  Prescription eyewear can be used to aid in forensic investigations. Until now, investigators and consulted eye professionals have been limited to a simple "match" or "no match" judgment. This article introduces optometry to a Web-based tool that can be used to assess the strength of a match between spectacle prescriptions and recorded patient information.
  
  
  METHODS
  Three databases with more than 385,000 individual prescriptions were used to create the Web tool that calculates the frequency with which a prescription occurs in various U.S. populations. A search for any prescription in the tool's database will result in a report of the number of times a given prescription occurred in the queried database(s) as well as the calculated frequency with which the combination of the given sphere power, cylinder power and axis are likely to occur.
  
  
  RESULTS
  Practical application of the Web tool in 2 published cases has shown matches with frequency of occurrence of 5.33 x 10(-6) and 2.66 x 10(-6), respectively. This application currently is being used by the Joint POW/MIA Accounting Command Central Identification Laboratory (JPAC-CIL) and other agencies when optical materials are available in forensic settings. Further, this application currently is contributing evidence in an active murder case.
  
  
  CONCLUSIONS
  The creation of this easy-to-use Web tool allows eye care professionals to provide strong statistical assessments when serving as consultants to forensic investigators.
authors: Wilford Hall Medical Center, San Antonio, TX 78236, USA. randall.collins@lackland.af.mil
authors: Randall S
authors: RS
authors: Collins
authors: Gregory E
authors: GE
authors: Berg
mesh_terms: D019992:Databases as Topic; D005139:Eyeglasses; D044707:Forensic Sciences / Q000379:methods* / Q000706:statistics & numerical data; D006801:Humans; D020407:Internet; D055656:Prescriptions; D014481:United States