Table 1.

Grading of objective parameters

Objective parameters	Observation
	Grade 0	Grade 1	Grade 2	Grade 3
Schirmer’s test	Level of wetting of tear strip above 15 mm in 1 min	Level of wetting of tear strip above 10 mm - 15mm in 1 min	Level of wetting of tear strip above 5 mm - 10 mm in 1 min	Level of wetting of tear strip at 1 mm - 5 mm in 1 min
Tear break-up time	The appearance of dry spots after 15 sec	The appearance of dry spots between 10 and 15 sec	The appearance of dry spots between 5 and 10 sec	The appearance of dry spots within 5 sec