. 2012 Jan 23;141(2 Suppl):e1S–e23S. doi: 10.1378/chest.11-2290

Table 3.

—[Section 4.0] VTE/DVT Prophylaxis and Treatment Studies

Study/Year	Patient Population	Study Design	Method of Preference Elicitation	Therapy	Outcomes Considered	Context	Summary of Results
Dranitsaris et al¹⁹/2009	24 volunteers (general public)	Cross-sectional interview	TTO	D 10 d/ D 35 d/ W	Major bleed	VTE prophylaxis	The disutility associated with one episode of DVT was greater, on average, than the disutility associated with 1.5 bleeds. When asked directly, 45.8% of patients chose dalteparin for 10 d with a 6.6% chance of major GI bleed, followed by warfarin (41.6%) with a 4.5% chance of bleed, and then by dalteparin for 35 d (12.5%) with a 6.6% chance of bleed.
					Symptomatic DVT
					Monitoring requirements
Locadia et al²⁰/2004	124 patients receiving VKA	Cross-sectional interviews with decision analysis	TTO	VKA	Nonfatal stroke	VTE treatment (prophylaxis)	Across a range of rates of recurrence of DVT without treatment from 5% to 15% (VTE risk reduced to 2% with treatment and a 3% risk of major bleeding event), participants’ treatment thresholds were variable (23% would always choose treatment, 30% would always reject treatment, the remainder would reject treatment between 5% and 15% risk of VTE). See Table 1 for additional HSUs
					PTS
					No treatment
					DVT
					Pulmonary embolism
					GI bleed
					Muscular bleed
					Treatment with VKA
					Burden
Locadia et al²¹ 2004	54 patients previously or currently being treated with VKA who previously experienced a thrombotic event	Repeated interviews (two interviews conducted 2 wk apart)	1. Conventional TTO method	VKA	Hospitalization after a serious accident	Use of anticoagulants for VTE, PTS, major bleed (prophylaxis)	Health state values differed significantly among the three methods. All participants ranked five health states; the average ordering of health states was as follows:
			2. Chained TTO method		DVT		1. Treatment with oral anticoagulants (HSU ∼0.75-0.95 across three methods of HSU elicitation)
			2. Chained TTO method		Pulmonary embolism		2. DVT (HSU ∼0.6-0.85)
			3. Rank ordering of health states		GI bleed		3. Muscular bleed (HSU ∼0.2-0.6)
			3. Rank ordering of health states		Muscular bleed		4. GI bleed (HSU ∼0.15-0.5)
			4. Direct rating of health states on a 0-100 scale		Treatment with oral anticoagulant		5. Pulmonary embolism (HSU ∼0.12-0.5)

D = dalteparin. See Table 1 and 2 legends for expansion of other abbreviations.