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Table 1 Model input parameters

From: Dabigatran versus warfarin under standard or pharmacogenetic-guided management for the prevention of stroke and systemic thromboembolism in patients with atrial fibrillation: a cost/utility analysis using an analytic decision model

Parameter Baseline Range for sensitivity analysis Distribution Reference(s)
Event probabilities
Percentage of INR time in therapeutic range (2-3) in warfarin usual standard dosing 64% 55-69% Beta [16]
Proportion of INR time range below therapeutic range (<2) 54% 45-60% [13]
Percentage of increasing of TTR by warfarin pharmacogenetic guided dosing 7.3% 0-30% [13]
Risk of major bleedings INR in therapeutic range 1.4% 0.9-2.3% [32, 33]
Relative risk of major bleedings INR above therapeutic range 1 - Fixed (reference)
Relative risk of major bleedings INR below therapeutic range 4.7 3.57-10 Log-normal
Relative risk of major hemorrhagic event dabigatran 150 mg vs warfarin 0.93 0.81-1.07 [16, 17, 28, 29]
Major hemorrhagic events (warfarin treatment) Proportion intracranial 42% 20-45% Beta [24, 31]
Proportion extracranial 58% 55-80% [31]
Proportion major hemorrhagic events Dabigatran 150 mg % Intracranial  12.6% 6.3-13.4% [14, 1820]
% Extracranial 90.4% 86.6-93.7
Risk of major thromboembolic events INR in therapeutic range 2.4% 1.2-4.9 [32, 34]
Relative risk of major thromboembolic events INR above therapeutic range 3.5 2.8-44 Log normal  
Relative risk of major thromboembolic events INR below therapeutic range 0.9 0.6-1.3
Relative risk of major thromboembolic events dabigatran 150 vs warfarin Stroke and systemic embolism 0.66 0.53-0.82 [16]
MI 1.38 1-1.91
PE 1.61 0.76-3.42
Major thromboembolic events (warfarin treatment) % Stroke 52.5%   Fixed [35]
% Myocardial infarctus (MI) 12.5%
% Pulmonary embolism (PE) 30%
% Deep venous thrombosis (DVT) 5%
Complications Major hemorrhagic event intracranial No deficit 8%   [31, 36]
Mild deficit 16%   
Severe deficit 34%   
Death 42% (first month)   
Extracranial   2%   [31]
Major thromboembolismevent Stroke Month 1 : 8.3%   [24, 36, 37]
  Death Months 2 and 3 : 5.6% per month  
  Severe deficit 40.2%  
  Mild deficit 42.5%  
  No deficit 9.1%  
Death PE 12%   [38, 39]
Death DVT 6%   [38, 40]
Death IM 7%   [24]
Treatment discontinuation after a major event Intracranial hemorrhage 100% during the entire period   [26] and expert opinion
Extracranial hemorrhage 100% during 30 days  
Costs (CAD$)
Drug costs Dabigatran 150 mg 3.20/day 1-5 Gamma [41]
Warfarin 5 mg 0.074/day 0.03-0.1
LMWH 27.90/5 days - Fixed
INR monitoring (first year) SD-W 8.06/month 5-12 Gamma [42]
GT-W 5/month 2-8 Assumption
INR monitoring (subsequent years) 4.03/month 2-6 Assumption
Genetic tests (CYP2C9 and VKORC1) 615 100-1000 [43, 44]
One-time event treatment costs Ischemic stroke, no deficit 845 500-100 [43, 44]
Ischemic stroke, mild deficit 23772 15000-40000 [4345]
Ischemic stroke, severe deficit 42620 30000-60000 [4346]
Intracranial hemorrhage (ICH), non deficit 1067 25000-50000 [4345]
ICH mild deficit 21218 15000-25000 [4345]
ICH severe deficit 36451 25000-50000 [4345]
Subdural hematoma 31942 20000-45000 [4345]
Extra cranial hemorrhage 8146 5000-12000 [43, 44]
DVT 2576 1500-4000 [43, 44]
PE 8799 5000-9000 [43, 45]
MI 7177 5000-15000 [43, 45]
Post-event cost Severe disability stroke/ICH 6259/month 3000-10000 [4446]
Mild disability stroke/ICH 1855/month 1000-3000
Health utilities
Warfarin no event 0.95 0.95-0.98 Beta [21, 47, 48]
Dabigatran no event 0.95 0.95-0.98 [21, 47, 48]
Major bleeding ICH No deficit 0.51 0.15-0.60 [21, 47, 48]
Mild deficit 0.75 0.70-0.90
Severe deficit 0.95 0.90-0.95
Extracranial 0.80 0.75-0.85
Stroke No deficit 0.95 0.90-0.95 [21, 47, 48]
  Minor 0.75 0.70-0.90
  Severe 0.39 0.15-0.50
MI 0.84 0.80-0.90 [21, 47, 48]
PE 0.76 0.70-0.90 [21, 47, 48]
DVT 0.84 0.80-0.90 [21, 47, 48]