Assessment of Different Wetting Time and Paper Strip Size of Schirmer Test in Dry Eye Patients
Surawoot Suphakasem MD*, Manapon Lekskul MD*, Ram Rangsin MD, MPH, DrPH**
Affiliation : * Department of Ophthalmology, Phramongkutklao Hospital, Bangkok, Thailand, ** Department of Military and Community Medicine, Phramongkutklao College of Medicine, Bangkok, Thailand
Objective : To evaluate the correlation between different wetting time and paper strip size of Schirmer test with anesthesia in
dry eye patient. Finally the authors determined the agreement on using the Ocular Surface Disease Index (OSDI), index for
evaluate the severity of the dry eye patient, compare to the standard Schirmer test with anesthesia.
Material and Method: A prospective study was performed in 140 eyes of 70 subjects. All subjects had symptoms of dry eye
syndrome which was confirmed by Schirmer test with anesthesia before inclusion. The correlation between Schirmer test with
anesthesia at 1, 2, 3 and 4 minutes and standard 5-minute test of both 3 mm and 5 mm width of paper strip was evaluated
using intraclass correlation coefficient (ICC). The correlation between clinical questions and Schirmer test was documented
in Kappa value.
Results : The ICCs were higher than 0.8 after 2 minutes in both 3-mm and 5-mm width of paper strip. Furthermore, it
indicated that cut-off value for diagnosis of severe dry eye was 2.5 mm for 5-mm width of paper strip and 4.25 mm for 3-mm
width of paper strip at 2-minute measurement. The association between data from the OSDI and objective data from Schirmer
test were analyzed by Kappa statistic and showed poor agreement beyond chance (p = 0.591).
Conclusion : Our results suggested that shorter wetting time of 2-minute Schirmer test with anesthesia could be used instead
of the standard 5-minute test. The authors found that the 3-mm width of paper strip could be used instead of the standard 5-
mm width of paper strip as well.
Keywords : Dry eye, Schirmer test, ICC, Reliability
