Evaluation of the Schirmer tear test.

We used the Schirmer filter paper test to measure tear production in 10 healthy women after instillation of local anesthetic drops at the same time of day for 30 or 31 consecutive days. We found that it was not a reliable indicator of tear production. The results varied widely even on the same subjects many of whom would, according to the standards for interpretation of the test, have been judged to produce an inadequate amount of tears.