title: Neophyte Skill Judging Corneoscleral Lens Clearance.
abstract: OBJECTIVE
  This study examines the accuracy of neophyte clinicians' assessments of central corneal clearance (CCC) of a corneoscleral lens using lens center thickness (CT) as a biometric scale.
  
  
  METHODS
  A normal participant was fit with a corneoscleral lens on both eyes. Observers (n = 34) from the final semester of their fourth year in optometric clinical training were instructed to estimate the amount of CCC through the approximate geometrical center of the lens using a standardized script which included a photograph identifying various zones. Observer estimates were then compared against anterior segment-OCT (AS-OCT) values obtained during calibration.
  
  
  RESULTS
  Mean observer estimates of central corneal clearances were OD 220.5 ± 121.microns (range 50 to 480 microns) and OS 398.0 ± 159.1 microns (range 140 to 800 microns). The mean AS-OCT values were OD 105.5 ± 11.microns (range 84 to 121 microns) and OS 340.8 ± 15.2 microns (range 315 to 362 microns). Mann-Whitney test was statistically significant for comparison of median values OD (177.0; p = 0.001) and OS (260.0; p = 0.012).
  
  
  CONCLUSIONS
  Neophyte clinicians in the final semester of their fourth year of optometric clinical training tend to significantly overestimate the amount of CCC in a normal subject with declining accuracy as the amount of clearance diminishes.
authors.affiliation: *OD, FAAO †OD ‡BS The Eye Center, Southern College of Optometry, Memphis, Tennessee (DGF, BS); and the Lasik Vision Institute, San Bruno, California (NC).
authors.forename: Daniel G
authors.initials: DG
authors.lastname: Fuller
authors.forename: Nancy
authors.initials: N
authors.lastname: Chan
authors.forename: Brenton
authors.initials: B
authors.lastname: Smith
mesh_terms: D000328:Adult; D001699:Biometry; D002982:Clinical Clerkship / Q000592:standards*; D003261:Contact Lenses; D003315:Cornea / Q000033:anatomy & histology*; D019781:Corneal Topography; D005260:Female; D006801:Humans; D008297:Male; D009907:Optometry / Q000193:education*; D011446:Prospective Studies; D017755:Prosthesis Fitting / Q000592:standards*; D012030:Refractive Errors / Q000534:rehabilitation; D012590:Sclera / Q000033:anatomy & histology*