The repeatability of discrete and continuous anterior segment grading scales

Optom Vis Sci. 2000 May;77(5):244-51. doi: 10.1097/00006324-200005000-00011.


Purpose: To investigate the repeatability of three anterior segment clinical grading scales: 1) verbal descriptors scale (VDS), 2) photographic matching scale (PS), and 3) continuous matching scale (CS).

Methods: Five optometrists graded 30 slides each of 3-9-o'clock staining, bulbar redness, and palpebral conjunctival roughness twice, separated by at least a day. VDS and PS were five-point scales (0-4) with half grades permitted. The CS was a 5-second, 240-frame video movie generated using morphing software. PS and CS grading was done with references presented on a computer screen.

Results: Averaged across observers, the test-retest intraclass correlation, correlation coefficient of concordance, and Pearson's r ranged from 0.95 to 0.99 (all p < 0.001). Coefficients of repeatability using CS to grade all three ocular conditions ranged between 0.31 and 0.49. The corresponding PS and VDS coefficients of repeatability ranged between 0.37 and 0.49; PS generally had better repeatability than VDS.

Conclusions: Each of the clinical grading scales was reliable. The coefficients of repeatability showed that bulbar redness and palpebral conjunctival roughness were graded with higher precision using CS.

Publication types

  • Comparative Study

MeSH terms

  • Anterior Eye Segment / pathology*
  • Conjunctiva / blood supply*
  • Conjunctiva / pathology
  • Conjunctival Diseases / classification*
  • Conjunctival Diseases / pathology
  • Diagnostic Techniques, Ophthalmological
  • Fluorophotometry
  • Humans
  • Hyperemia / classification*
  • Hyperemia / pathology
  • Observer Variation
  • Orbit / blood supply*
  • Orbit / pathology
  • Photography
  • Reproducibility of Results