Abstract
Purpose: :
To analyze repeatability of subjective and objective grading of meibography images.
Methods: :
Meibography images of 24 subjects (female= 14; mean age= 46; range= 19 - 69 years) were classified in two different sessions (day 1 vs. 2) by two experienced observers. Loss of meibomian glands (MGL) was classified three times applying three different grading scales in randomized order: A four grade pictorial grading scale (4S) (degree 0= No MGL; 1=<25% MGL; 3= 25% to 75% MGL; 3= >75% MGL) a five grade pictorial grading scale (5S) (degree 0= No MGL; 1=<25% MGL; 3= 25% to 50% MGL; 3= 50% to 75%; 4= >75% MGL) and objectively by digital analyses (DA) obtaining Image J Software (degree: 0 - 100 MGL). Observers were masked to results. Differences between observers and session were analyzed by repeated measurements ANOVA (or non-parametric equivalent) and Bland Altman plots and relations by Pearson correlation (or non-parametric equivalent). 95% confidence intervals (CI) were calculated from the distributions of differences between observer and observations
Conclusions: :
Intra-observer and inter-observer agreement was better in digital grading followed by the 5 grade scale and the 4 grade scale being the least repeatable one.
Keywords: anterior segment • imaging/image analysis: clinical • conjunctiva