title: The usefulness of waveform score from the ocular response analyzer.
abstract: OBJECTIVE
  To study the usefulness of the Waveform Score from the ocular response analyzer (ORA).
  
  
  METHODS
  Both eyes of sixty-four normal Chinese adults were measured by the ORA. An experienced practitioner who was masked to the score evaluated the waveforms. Four measurements were obtained from each eye, and the average was considered as the gold standard. Agreement was compared for the mean of different multiple measurements to the gold standard.
  
  
  RESULTS
  There was no significant difference between the gold standard and the mean of different multiple measurements for all ORA parameters. The Waveform Score of 512 signals (four measurements from each eye of 64 subjects) ranged from 1.58 to 9.06. When the best signal value of four measured signals from each eye was considered, the lowest score was 3.60 from 128 eyes. The lower 10th percentile from all signals had Waveform Scores <3.48.
  
  
  CONCLUSIONS
  If the Waveform Score provides information on the reliability of the signals, a score <3.50 may indicate an unreliable signal, and the signal should be discarded. We also recommend taking three measurements with all the signals having a Waveform Score of 3.50 or above to increase the precision.
authors.affiliation: *PhD, FAAO †BSc(Hons) School of Optometry, The Hong Kong Polytechnic University, Hong Kong SAR, China.
authors.forename: Andrew K C
authors.initials: AK
authors.lastname: Lam
authors.forename: Davie
authors.initials: D
authors.lastname: Chen
authors.forename: Jimmy
authors.initials: J
authors.lastname: Tse
mesh_terms: D000328:Adult; D003315:Cornea / Q000502:physiology*; D003941:Diagnostic Techniques, Ophthalmological / Q000295:instrumentation*; D004548:Elasticity / Q000502:physiology*; D005260:Female; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology*; D008297:Male; D015203:Reproducibility of Results; D012189:Retrospective Studies