Fishman comment: Blink analysis is a simple yet under appreciated technique that helps dry eye diagnosis and treatment. This paper illustrates the utility of blink analysis.

Authors: Kunihiko Hirosawa1,2, Takenori Inomata1,2,3,4,5*, Jaemyoung Sung1, Masahiro Nakamura2,6, Yuichi Okumura1,2,4, Akie Midorikawa‐Inomata5, Maria Miura1,2, Kenta Fujio1,2,

Yasutsugu Akasaki1,2, Keiichi Fujimoto1,2, Jun Zhu1,7, Atsuko Eguchi5, Ken Nagino5,

Mizu Kuwahara1,2, Hurramhon Shokirova1, Ai Yanagawa2 & Akira Murakami1,2,3

Abstract: Various symptoms of the dry eye disease (DED) interfere with the quality of life and reduce work productivity. Therefore, screening, prevention, and treatment of DED are important. We aimed

to investigate the potential diagnostic ability of the maximum blink interval (MBI)(the length of time participants could keep their eyes open) with disease‐specific questionnaire for DED. This cross‐sectional study included 365 patients (252 with DED and 113 without DED) recruited between September 2017 and December 2019. Discriminant validity was assessed by comparing the non‐DED and DED groups based on the MBI with a Japanese version of the Ocular Surface Disease Index (J‐OSDI) and tear film breakup time (TFBUT) with J‐OSDI classifications. The MBI with J‐OSDI showed good discriminant validity by known‐group comparisons. The positive and predictive values of MBI with J‐OSDI were 96.0% (190/198 individuals) and 37.1% (62/167 individuals), respectively. The area under the receiver operating characteristic curve (AUC) of MBI with J‐OSDI was 0.938 (95% confidence interval 0.904–0.971), the sensitivity was 75.4% (190/252 individuals), and the specificity was 92.9% (105/113 individuals), which are similar to the diagnostic ability of TFBUT with J‐OSDI (AUC 0.954). In conclusion, MBI with J‐OSDI may be a simple, non‐invasive screening test for DED.