Table 1.

Dry eye disease definitions proposed from 1995 onwards.

Group	Instability of Tear Film	Global Consensus
NEI/Industry Workshop on Clinical Trials in Dry Eye (1995) [10]	−	−
Pflugfelder (2003) [11]	P	−
TFOS DEWS I (2007) [12]	S	+
TFOS DEWS II (2017) [8]	S	+
AAO PPP (2018) [9]	P	−
Japanese Dry Eye Research Group (2006) [13]	−	−
Korean Corneal Disease Study Group [14]	P	−
Chinese Medical Association Ophthalmic Branch Corneal Group [15,16]	P	−
Asia Dry Eye Society 2017 [7]	P	+
Japanese Dry Eye Research Group (2016) [17]	P	−
New Global Consensus Definition	P	−

P and S indicate if tear instability was a primary (P) or secondary (S) criterion in the definition, respectively. + and − in the Global Consensus column indicate if the definition was approved by consensus of an international group or organization. NEI: National Eye Institute; TFOS: Tear Film & Ocular Surface Society; DEWS: International Dry Eye Workshop; AAO PPP: American Academy of Ophthalmology Preferred Practice Patterns.