modified schirmer's test in normal eyes: open versus closed eyes and 1-minute versus 5-minute tests

purpose : to assess the results of 1-minute and 5-minute schirmer's test (st) when the eyes are open (sto) and closed (stc) in normal participants. methods : in a comparative, observational case series study, 34 normal volunteers were included in the study. inclusion criteria were normal ophthalmologic findings except for refractive errors, no use of contact lenses, no history of previous medical or ophthalmic problems, and no current use of medications. sto and stc in 1 and 5 minutes time were performed separately for all subjects with an interval of at least 24 hours using whatman no. 41 (5x60 mm) with bended end of the paper inserted into the lateral side of the lower conjunctival fornix. results : there were 19 females and 15 males with a mean age of 20.8 years (range: 18-23). mean value of stc was significantly less than sto in both 1 minute and 5 minute tests. one-minute sto and stc showed a significantly less wetting than 5-minute test. normal distribution was observed for all values. a significant correlation were found between 1-minute and 5-minute tests in both sto and stc therefore, two equations were proposed to calculate the 5-minute from 1-minute st. statistical analysis did not provide a reliable equation for calculating the standard st (5-minute sto) from the most comfortable state (1-minute stc). conclusion : faster and more comfortable st (1-minute) is a reliable test to calculate the 5-minute st in both open and closed eye, using the provided equations. the 1-minute stc is not a reliable test to calculate the 5-minute sto.   iranian journal of ophthalmology 200921(1):52-56 © 2009 by the iranian society of ophthalmology