Table 1.

 Levels of retinopathy according to the Scottish Diabetic Retinopathy Grading Scheme 2003

Retinopathy	Description	Outcome
R0	No diabetic retinopathy anywhere	Re-screen in 12 months
R1 (mild)	Background diabetic retinopathy (BDR), mild	Re-screen in 12 months
	At least one dot haemorrhage or microaneurysm with or without hard exudates
R2 (moderate)	BDR, moderate Four or more blot haemorrhages (ie, ⩾AH* standard photograph 2a) in one hemifield only. (Inferior and superior hemifields are delineated by a line passing through the centre of the fovea and the optic disc)	Re-screen in 6 months (or refer to ophthalmology if this is not feasible)
R3 (severe)	BDR, severe	Refer to ophthalmology
	Any of the following features
	Four or more blot haemorrhages (ie, ⩾AH* standard photograph 2a) in both inferior and superior hemifields
	Venous beading (ie, ⩾AH* standard photograph 6a)
	IRMA (ie, ⩾AH* standard photograph 8a)
R4 (proliferative)	Proliferative diabetic retinopathy	Refer to ophthalmology
	PDR
	Any of the following features
	New vessel
	Vitreous haemorrhage
R5 (enucleated)	Enucleated eye	Re-screen 12 months
		(other eye)
R6	Not adequately visualised	Technical failure

AH*, Airlie house standard photographs.¹⁴