The effectiveness of early lens extraction with intraocular lens implantation for the treatment of primary angle closure glaucoma

1. Patient-centred outcome: Health Status, assessed by the EQ-5D at 6, 12, and 24 months with the major outcome assessment at 36 months from the date of randomisation
2. Clinical outcome: IOP at 3 year final assessment
3. Economic outcome: Incremental cost per quality adjusted life year (QALY) gained with QALYs based on the responses to the EQ-5D

The following will be assessed at 6, 12, and 24 months with the major outcome assessment at 36 months from the date of randomisation:

1. Patient-centred:
Patient reported, using:
1.1. A glaucoma specific utility instrument (GPI)
1.2. A vision specific health profile measure (NEI-VFQ25)

2. Clinical:
2.1. Need for trabeculectomy
2.2. Progressive visual field loss
2.3. Best-corrected visual acuity (ETDRS)
2.4. Extension of angle closure (degrees of appositional and synechial angle closure)
2.5. Escalation of therapy
2.6. Number of anti-glaucoma medications
2.7. Intolerance of medications
2.8. Incidence of acute attacks of angle closure

3. Economic:
Costs will be based on resource use data. Costs to the NHS and patients:
3.1. Use of health services for glaucoma related events or treatments
3.2. Patient costs (treatments, spectacles, travel to health services, sick leave)
3.3. Need for alternative management for glaucoma (e.g., surgery, drugs)
3.4. Other use of health services: visits to i) GP, ii) nurse, iii) optometrists