Table 1. Cost assumptions, utility value, and transition probabilities in the decision analysis of screening for diabetic retinopathy.

Parameter			Value
Annual direct cost (New Taiwan dollars)
	Screening cost*		2298
	Drug cost†		10857
	Regular clinic fees‡		509
	Laser photocoagulation§		10970
	Vitrectomy||		10840
	Total		35474
Annual indirect cost (New Taiwan dollars)
	Gross Domestic Product (GDP)		452168
Utility (quality of life) value13
	No diabetic retinopathy (DR)		0.94 ± 0.11
	Non-proliferative diabetic retinopathy (NPDR)		0.87 ± 0.14
	Proliferative diabetic retinopathy (PDR)		0.83 ± 0.09
	Legal blindness		0.81 ± 0.08
Annual transition probability (%)12
	No DR	→ Mild NPDR	7.37
	Mild NPDR	→ Moderate NPDR	19.37
	Moderate NPDR	→ Severe NPDR	17.41
	Severe NPDR	→ PDR	28.95
	PDR	→ Legal blindness	21.1

*: Screening cost includes clinician’s fee, vision examination, pupil dilation, slit-lamp contact-mirror funduscopy, funduscopic examination, hemoglobin A1c, simultaneous multichannel autoanalyse-12 test (albumin, alkaline phosphatase, bilirubin, blood urea nitrogen [BUN], calcium, total cholesterol, creatinine, glucose, phosphorus, aspartate aminotransferase [AST, GOT], total protein, and uric acid), and manpower cost.

†: According to the drug usage distribution from the Taiwanese Association of Diabetes Educators (TADE) study in 2004 and the payment of National Health Insurance.

‡: Regular clinic fees includes the clinician’s fee and pharmacist’s fee.

§: Laser photocoagulation cost includes panretinal photocoagulation, 2 fundus color photos, and fluorescein angiography (FAG).