Table 1. Ion concentrations in artificial tear samples from sub-types and different severity stages.

Subtype-differentiation
Ions	Control (mmol L–1)	Sample 1 (MGD) (mmol L–1)	Sample 2 (LGD) (mmol L–1)	Sample 3 (MGD + LGD) (mmol L–1)
Na+	133.2	136.1	142.2	145.1
K+	24.0	24.6	24.9	25.4
Ca2+	0.80	0.82	0.84	0.86

Severity stages
Ions	Normal (mmol L–1)	Mild stage (mmol L–1)	Moderate stage (mmol L–1)	Severe stage (mmol L–1)
Na+	135	145	155	165
K+	24	25	26	27
Ca2+	0.80	0.85	0.90	0.95