The DRy eye Outcome and Prescription Study (DROPS) is a large observational multicentre study exploring the 'real world' effectiveness of artificial tears in dry eye disease and determinants of efficacy. The aim is to include at least 635 symptomatic dry eye patients who are prescribed artificial tears. All trainees and fellows in London are invited to become collaborators: collaborators are asked to consent patients, assess signs at baseline, and give patients questionnaires at baseline and 4 weeks (for home completion). In tandem, we are conducting a qualitative review of ophthalmologists' prescribing behaviours for dry eye disease.

Inclusion Criteria:

• adult patients (18 years and over) with symptoms* of dry eye disease (with or without signs, with or without blepharitis) who start one or more artificial tears. *Symptoms of dry eye disease include: foreign body sensation, dryness, irritation, itching, burning, stinging or grittiness. When signs are present, symptoms of visual disturbance such as poor vision and blurred vision are sufficient as a symptom of dry eye disease too
• must have best corrected visual acuity in at least one eye of at least 6/12.

Exclusion Criteria:

• lacks capacity (e.g. dementia)
• poor understanding of English
• active other apparent ocular surface disease (including conjunctivitis, abrasion, recurrent erosion syndrome, episcleritis, inflamed pingueculum or pterygium, tumour, infectious keratitis).
• immune ocular pathology (including scleritis and uveitis).
• recent (within the last 3 months) or planned ocular surgery or intravitreal injections.
• current use of other ocular medication, e.g. antiglaucoma drops, g ciclosporine.
• use of artificial tears or ointment in the last 1 month.
• gross lid abnormalities, including significant ectropion or entropion; facial nerve palsy; thyroid eye disease; trichiasis.

For the qualitative interview study:

Subject inclusion criteria

- London NHS Consultant with at least 6 months experience as a Consultant, with a special interest in Cornea and External Diseases, Accident and Emergency and Primary Care, or General Ophthalmology

Patients attending hospital ophthalmology outpatient clinics and emergency care (Eye Casualty). Dry eye can be the presenting problem or a secondary problem.