Schirmer test. II. A clinical study of its repeatability.

In most parts of the world, the Schirmer test (ST) is still the main test used by optometrists for the assessment of tear adequacy in the screening of potential contact lens wearers and as an aid in the diagnosis of "dry" eye. We tested the reliability of a 1-min ST in nine normal Hong Kong-Chinese (HK-Chinese) subjects during five to seven visits over a period of 2 weeks. For 4 of the subjects, the test consistently measured 0 mm/1 min, and 68% of the test results were less than 6 mm/1 min, a value suggested as the lower limit for normal asymptomatic eyes. The results obtained were inconsistent and it is concluded that the ST is unreliable and of little clinical value in this population.