title: The disc damage likelihood scale: reproducibility of a new method of estimating the amount of optic nerve damage caused by glaucoma.
abstract: OBJECTIVE
  The major objective of this study was to test the reproducibility of a new method of estimating the amount of optic disc damage in patients with glaucoma.
  
  
  METHODS
  The Disc Damage Likelihood Scale (DDLS) is based on the appearance of the neuroretinal rim of the optic disc corrected for disc diameter. The eight stages, extending from no damage to far advanced damage, are based on the width of the neuroretinal rim or the circumferential extent of absence of neuroretinal rim. Reproducibility was measured by two masked observers staging 48 optic nerve stereoscopic photographs by two different methods, the cup/disc ratio (c/d) and the DDLS. Also, reproducibility was assessed by three observers examining 34 eyes of 24 patients.
  
  
  RESULTS
  With regard to the photographs, the intraobserver and interobserver reproducibility was better using the DDLS than the c/d ratio (98% versus 85% for intraobserver of reproducibility, and 85% versus 74% for interobserver reproducibility). The DDLS correlated better with the Humphrey Visual Field than did any Heidelberg Retina Tomograph parameter.
  
  
  CONCLUSIONS
  In a clinical setting, the DDLS is as reproducible as, or more reproducible than, the c/d ratio system of estimating the amount of disc damage in patients with glaucoma.
authors.affiliation: William and Anna Goldberg Glaucoma Research Laboratories, Wills Eye Hospital, Jefferson Medical College, Philadelphia, Pennsylvania, USA.
authors.forename: George L
authors.initials: GL
authors.lastname: Spaeth
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Henderer
authors.forename: Connie
authors.initials: C
authors.lastname: Liu
authors.forename: Muge
authors.initials: M
authors.lastname: Kesen
authors.forename: Undraa
authors.initials: U
authors.lastname: Altangerel
authors.forename: Atilla
authors.initials: A
authors.lastname: Bayer
authors.forename: L Jay
authors.initials: LJ
authors.lastname: Katz
authors.forename: Jonathan
authors.initials: J
authors.lastname: Myers
authors.forename: Douglas
authors.initials: D
authors.lastname: Rhee
authors.forename: William
authors.initials: W
authors.lastname: Steinmann
mesh_terms: D003941:Diagnostic Techniques, Ophthalmological; D005901:Glaucoma / Q000150:complications / Q000175:diagnosis*; D006801:Humans; D016013:Likelihood Functions; D015588:Observer Variation; D009898:Optic Disk / Q000473:pathology*; D009901:Optic Nerve Diseases / Q000175:diagnosis* / Q000209:etiology; D010781:Photography; D015203:Reproducibility of Results; D014794:Visual Fields