Table 1. Schein questionnaire.

There are 6 questions, as follows:   1. Do your eyes ever feel dry?   2. Do you ever feel a gritty or sandy sensation in your eye?   3. Do your eyes ever have a burning sensation?   4. Are your eyes ever red?   5. Do you notice much crusting on your lashes?   6. Do your eyes ever get stuck shut in the morning?
Symptoms are graded as:   • rarely   • sometimes   • often or   • all of the time