Table 1.
Parameters used in the economic evaluation
| Basea | Parameters for sensitivity analysis | Sourcesd | |||
|---|---|---|---|---|---|
| Minb | Maxb | Probability distributionc | |||
| Clinical and epidemiological | |||||
| Population | |||||
| (n) Patients followed per year | 1000 | – | – | – | Model assumption |
| Age of patients | 62.5 | 60 | 75 | Normal (62.50; 3.75) | Model assumption based on TERRA registry [1], Connock 2007 [2], CADTH 2014 [16] |
| Time in therapeutic range | |||||
| [AC] (%) TTR< (below range) | 15.20% | 7.9a% | 22.5% | Dirichlet | Tajer 2017 (TERRA registry) [1] |
| [AC] (%) <TTR< (in range) | 66.60% | 34.70% | 98.50% | Dirichlet | Tajer 2017 (TERRA registry) [1] |
| [AC] (%) <TTR (above range) | 18.20% | 9.5% | 26.9% | Dirichlet | Tajer 2017 (TERRA registry) [1] |
| (RR) Relative benefit of AC vs no AC for <TTR< | 1.11 | 1.09 | 1.2 | LogNormal (0.1; 0.0) | See Methods |
| Risks of events according to TTR | |||||
| (Pr) Thrombosis/TTR< | 2.72% | 2.00% | 3.40% | Beta (58.7; 2,100.3) | Connock 2007 [2] |
| (Pr) Thrombosis/<TTR< | 0.73% | 0.60% | 0.90% | Beta (65.3; 8,880.3) | Connock 2007 [2] |
| (Pr) Thrombosis/<TTR | 0.81% | 0.60% | 1.00% | Beta (65.1; 7,968.3) | Connock 2007 [2] |
| (Pr) Minor bleeding/TTR< | 6.10% | 4.60% | 7.60% | Beta (62.1; 955.2) | Connock 2007 [2] |
| (Pr) Minor bleeding/<TTR< | 4.80% | 3.60% | 5.90% | Beta (65.0; 1,302.5) | Connock 2007 [2] |
| (Pr) Minor bleeding/TTR< | 11.30% | 8.50% | 14.10% | Beta (57.6; 452.4) | Connock 2007 [2] |
| (Pr) Major bleeding/TTR< | 1.20% | 0.90% | 1.50% | Beta (60.1; 5,078.0) | Connock 2007 [2] |
| (Pr) Major bleeding/<TTR< | 0.90% | 0.70% | 1.20% | Beta (51.6; 5,554.7) | Connock 2007 [2] |
| (Pr) Major bleeding/TTR< | 3.40% | 2.50% | 4.20% | Beta (60.7; 1,741.1) | Connock 2007 [2] |
| (Pr) Permanent disability/major hemorrhagic event | 14.00% | 10.50% | 17.50% | Beta (54.9; 337.2) | Connock 2007 [2] |
| (Pr) Permanent disability/thrombosis | 63.80% | 47.80% | 79.70% | Beta (22.5; 12.8) | Connock 2007 [2] |
| (Pr) Death/major bleeding | 14.00% | 10.50% | 17.50% | Beta (54.9; 337.2) | Connock 2007 [2] |
| (Pr) Death/thrombosis | 21.00% | 15.80% | 26.30% | Beta (50.4; 189.4) | Connock 2007 [2] |
| (RR) Death/disability | 2.25 | 1.5 | 3 | LogNormal (0.8; 0.2) | Connock 2007 [2] & Sundberg 2003 [48] |
| Utilities | |||||
| (U) Argentinian population | – | Janssen 2019 [29] | |||
| Disutility due to anticoagulation therapy | 0.01 | 0.01 | 0.02 | Beta (98.7; 7,492.6) | Pink 2011 [30] |
| Ratio of U weights [Acute event minor bleeding]/[No event] | 0.98 | 0.78 | 1 | Gamma (100.00; 0.01) | Calculated from Connock 2007 [2] |
| Ratio of U weights [Acute event thrombosis]/[No event] | 0.77 | 0.62 | 0.93 | Gamma (100.00; 0.01) | Calculated from CADTH 2014 [16] |
| Ratio of U weights [Acute event major bleeding]/[No event] | 0.75 | 0.60 | 0.90 | Gamma (100.00; 0.01) | Calculated from CADTH 2014 [16] |
| Ratio of U weights [Permanent disability]/[No event] | 0.54 | 0.43 | 0.65 | Gamma (100.00; 0.01) | Calculated from CADTH 2014 [16] |
| Use of resources and costs (AR $) | |||||
| ($) CoaguChek INR determination | $164 | $139 | $245 | Gamma (38.60; 4.26) | Roche Diagnostics Argentina, 2021e |
| ($) LAB: Reagents (per sample) | $31 | $25 | $38 | Gamma (100.00; 0.31) | Roche Diagnostics Argentina, 2021e |
| ($) LAB: Syringe | $30 | $24 | $36 | Gamma (100.00; 0.30) | IECS BCU, 2021 [37] |
| ($) LAB: Needle | $20 | $16 | $24 | Gamma (100.00; 0.20) | IECS BCU, 2021 [37] |
| ($) LAB: Citrated tube | $42 | $27 | $50 | Gamma (51.11; 0.82) | IECS BCU, 2021 [37] |
| ($) LT total gross salary | $56,448 | $45,159 | $67,738 | Gamma (100.00; 564.48) | Collective labor agreement 2021 [49] |
| ($) Add monthly costs for AC per 1000 patients | $116,728 | $0 | $ 222,304 | Gamma (17.10; 6,824.39) | See Methods |
| ($) Permanent disability, monthly cost | $77,452 | $58,089 | $96,815 | Gamma (64.00; 1,210.19) | See Methods |
| ($) Thrombosis event | $406,018 | $242,219 | $560,616 | Gamma (26.02; 15,605.34) | Giorgi 2015 [31] (updated to 2021) |
| ($) Minor bleeding event | $293,871 | $107,350 | $183,652 | Gamma (237.33; 1,238.21) | Giorgi 2015 [31] (updated to 2021) |
| ($) Major bleeding event | $651,312 | $454,058 | $993,583 | Gamma (23.32; 27,932.76) | Giorgi 2015 [31] (updated to 2021) |
| LAB: LT time per extraction of each sample (min) | 10.4 | 8 | 12.8 | Gamma (75.11; 0.14) | Leung 2006 [50] |
| LAB: LT time per centrifugation of each sample (min) | 15 | 12 | 18 | Gamma (100.00; 0.15) | Funk 2008 CLSI [51] |
| LAB: Number of samples (per centrifugation) | 5 | 3 | 10 | Gamma (8.16; 0.61) | Assumption |
| LAB: LT processing time per sample (min) | 2 | 1 | 3 | Gamma (16.00; 0.13) | Model assumption |
| POC: LT time per extraction of each sample (min) | 2.2 | 1.8 | 2.7 | Gamma (100.00; 0.02) | Fitch 1999 [52] |
| POC: LT processing time per sample (min) | 1 | 0.5 | 2 | Gamma (7.11; 0.14) | CoaguChek XS user manual [19] |
| LT productivity (minutes worked per month) | 8400 | 6,300 | 8,400 | Gamma (256.00; 32.81) | Assumption |
| (n) INR determinations per year (per patient) | 12 | 9.6 | 14.4 | Normal (12.0; 1.20) | Model assumption |
| Others | |||||
| (%) Discount rate | 5% | 0% | 10% | – | Guías Mercosur [53] |
| (USD) GDPpc | 8442 | – | – | – | World Bank 2021 [54] |
| Exchange rate (AR per 1 USD) | $143 | $104 | $183 | Gamma (51.91; 2.75) | dolarhoy.com (Sep 8, 2021) [32] |
| (%) Market share AC year 1 | 20% | – | – | – | Assumption |
| (%) Market share AC year 2 | 40% | – | – | – | Assumption |
| (%) Market share AC year 3 | 60% | – | – | – | Assumption |
| (%) Market share AC year 4 | 80% | – | – | – | Assumption |
| (%) Market share AC year 5 | 100% | – | – | – | Assumption |
Base estimates, minimums, maximums, assumed probability distributions and sources. Costs expressed in local currency (Argentine pesos) Argentina, 2021
AC anticoagulation clinic, GDPpc gross domestic product per capita, INR international normalized ratio, LAB laboratory, LT laboratory technician, POC point of care, Pr probability, RR relative risk, TTR time in therapeutic range, TTR< below therapeutic range, <TTR< in therapeutic range, <TTR above therapeutic range, U utility
aValues used for the base (deterministic) estimates
bSee methods for more details on the calculation of minimum and maximum values
cProbability distributions were selected according to methodological recommendations. The parameters of the distributions were derived using the method of moments, assuming the mean values as the base values and the standard deviations as 1/4 of the width of the interval between the maximum and minimum values (see Methods)
dSee Methods and References sections for details of data sources.
eValues provided by Roche Diagnostics Argentina.