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Published on: May 25, 2022
Comparison of the Ocular Surface Disease Index and the Symptom Assessment in Dry Eye Questionnaires for Dry Eye
Raul Martin1, Emo Research Group1
1Instituto Universitario de Oftalmobiología Aplicada (IOBA), Universidad de Valladolid, Paseo de Belén, 17-Campus Miguel Delibes, 47011 Valladolid, Spain.
Background:
Patient-reported dry eye symptoms (DESs), assessed using the Ocular Surface Disease Index (OSDI) and the Symptom Assessment iN Dry Eye (SANDE) questionnaires, were compared in a large sample of patients.
Methods:
The correlation (Spearman coefficient) and agreement (Bland-Altman analysis) between the OSDI and SANDE questionnaire scores (with and without score normalization) were assessed in 1033 patients and classified according to the OSDI score as non-DES and DES in a cross-sectional analysis.
Results:
The normalized and non-normalized SANDE results were higher than the OSDI results in all samples (2.83 ± 12.40 (p = 0.063) and 2.85 ± 15.95 (p = 0.016), respectively) and in non-DES (p > 0.063) and DES (p < 0.001) with both OSDI cutoff values. Weak correlations were found (Spearman coefficient <0.53; p < 0.001) in all cases except DES (0.12, p = 0.126). Weak agreement was found with a Bland-Altman analysis of the normalized and non-normalized scores of both questionnaires (mean difference from -7.67 ± 29.17 (DES patients) to -1.33 ± 8.99 (non-DES patients) without score normalization, and from -9.21 ± 26.37 (DES patients) to -0.85 ± 4.01 (non-DES) with data normalization), with a statistically significant linear relationship (R2 > 0.32, p < 0.001). The SANDE questionnaire did not yield the same patient classification as OSDI. The same operative curves (ROC) of the SANDE normalized and non-normalized scores were used to differentiate among patients with DES using OSDI < 12 (0.836 ± 0.015) or OSDI < 22 (0.880 ± 0.015) cutoff values.
Conclusions:
Normalized and non-normalized data collected from the SANDE questionnaire showed relevant differences from those of the OSDI, which suggests that the results of the SANDE visual analog scale-based questionnaire provide different patient classifications than the OSDI score.

