Validation of TearLab Osmometer - Human Factor Usability Report

Inclusion Criteria: * Healthy volunteers representing the general population (a minimum of 120 subjects representing 50% of the total study population, * Otherwise healthy volunteers previously-diagnosed with moderate or severe chronic dry eye and/or Sjogrens syndrome and/or designated as dry eye disease subjects by the OSDI questionnaire (a minimum of 40 subjects representing 50% of the total study population), * Men or women, * Adult 18 years or older, * Contact lens wearers may participate, * Patients having undergone refractive surgery may participate, * Patients having undergone cataract surgery may participate Exclusion Criteria: * Eye pathology other than previously-diagnosed moderate or severe chronic dry eye and/or Sjogrens syndrome, Use of topical medication within the last 24 hours, * Eye drop usage within the last 2 hours, * Ocular surface staining within the last 2 hours, * Other invasive ocular diagnostic testing within the last 2 hours, * Crying within the last 30 minutes, * Eye makeup present on the eye lid within 10 minutes of tear collection, * Examination by slit lamp within 10 minutes of tear collection.