Table 1

Timing of outcome measurements

	Baseline	Post randomisation (months)
	Baseline	1	3	4	6	12	18	24
Clinical
Medical history	x
Humphrey visual field mean deviation	x			x		x		x
Esterman Visual Field	x							x
LogMAR visual acuity	x			x		x		x
Intraocular pressure	x			x		x		x
Standard clinical examination	x					x		x
Patient experience
NEI-VFQ-25	x			x		x		x
EQ-5D-5L*	x	x	x		x	x	x	x
HUI-3*	x	x	x		x	x	x	x
GUI*	x	x	x		x	x	x	x
Patient experience questions	x	x	x		x	x	x	x
Health economics
Healthcare utilisation (including hospital visits)				x		x		x
Participant cost				x		x		x
Participant time and travel							x

*Additional questionnaire undertaken immediately prior to trabeculectomy surgery; discrete choice experiment at 27 months;
GUI, Glaucoma Utility Index; HUI-3, Health Utility Index; LogMAR, logarithm of the mean angle of resolution; NEI-VFQ25, National Eye Institute Visual Function Questionnaire (25 items).