Table 1.
Model parameters and distribution used in the probabilistic sensitivity analyses
| Model parameter | Value | Probability distribution | Moments of the probability distribution ά/min, β/max | Source |
|---|---|---|---|---|
|
Discount rates |
|
|
|
|
| Cost discount rate |
4% |
Fixed |
- |
[14] |
| Outcome discount rate |
1.5% |
Fixed |
- |
[14] |
|
Costs (Euros)* |
|
|
|
|
| Cost of ankle brachial index test |
74† |
BETA Pert |
55.7;92.8 |
MUMC‡ |
| Annual cost of PAD treatment |
2369 |
GAMMA |
325.09;7.29 |
[18] |
| Annual cost of Aspirin |
10 |
Fixed |
|
[19] |
| Annual cost of Clopidogrel |
19 |
Fixed |
|
[19] |
| Costs of Amputation |
14343† |
BETA Pert |
10683;17804 |
[20] |
| Cost of AMI in first year |
25328 |
GAMMA |
100;253.27 |
[21] |
| Annual costs of MI treatment in subsequent years |
3584 |
GAMMA |
99.92;35.86 |
[21] |
| Cost of stroke in first year |
27964 |
GAMMA |
99.99;279.66 |
[21] |
| Annual costs of treatment of stroke in subsequent years |
10646 |
GAMMA |
99.99;106.47 |
[21] |
| Costs of bleeding |
3457 |
GAMMA |
99.87;34.61 |
[21] |
|
ABI test accuracy |
|
|
|
|
| Sensitivity |
0.90† |
BETA Pert |
0.68;1 |
[22] |
| Specificity |
0.95† |
BETA Pert |
0.71;1 |
[22] |
|
Incidence/prevalence of PAD |
|
|
|
|
| Prevalence of PAD |
0.184 |
BETA |
1372;6082 |
[6] |
| Annual incidence of PAD in 55–64 years aged |
0.005 |
BETA |
See Additional file 1 |
[23] |
| Annual incidence of PAD in 65–74 years aged |
0.007 |
BETA |
See Additional file 1 |
[23] |
| Annual incidence of PAD in 75–84 years aged |
0.008 |
BETA |
See Additional file 1 |
[23] |
| Annual incidence of PAD in >85 years aged |
0.010 |
BETA |
See Additional file 1 |
[23] |
|
Event probabilities |
|
|
|
|
| Probability of amputation in patients with no PAD |
0.003 |
BETA |
32;11734 |
[24] |
| Probability of AMI in patients with no PAD |
0.008 |
BETA |
89;11677 |
[24] |
| Probability of stroke in patients with no PAD |
0.008 |
BETA |
94;11672 |
[24] |
| Probability of amputation in PAD patients |
0.016 |
BETA |
140;8441 |
[24] |
| Probability of AMI in PAD patients |
0.013 |
BETA |
111;8470 |
[24] |
| Probability of stroke in PAD patients |
0.019 |
BETA |
165;8416 |
[24] |
| Probability of symptomatic PAD |
0.3 |
BETA |
138;320 |
[25] |
| Relative risk in PAD patients on low dose aspirin |
0.78 |
BETA |
25.45;7.2 |
[26] |
| Probability of bleeding in PAD patients on aspirin |
0.026 |
BETA |
255;9311 |
[27] |
| Relative risk in PAD patients on Clopidogrel |
0.616 |
BETA |
See Additional file 1 |
[28] |
| Probability of bleeding in PAD patients on Clopidogrel |
0.020 |
BETA |
191;9386 |
[27] |
|
Mortality in ‘untreated’ patients |
|
|
|
|
| Annual probability of death in PAD patients |
0.037 |
BETA |
323;8258 |
[24] |
| Probability of death in post Amputation |
0.155 |
BETA |
4297;21281 |
[29] |
| annual probability of death in post MI alive patients |
0.028 |
BETA |
521;17492 |
[24] |
| annual probability of death in post stroke alive patients |
0.031 |
BETA |
1212;37390 |
[24] |
|
Utility |
|
|
|
|
| PAD |
0.652 |
BETA |
0.8;0.4 |
[30] |
| Amputation |
0.45 |
BETA |
210.8;257.7 |
[31] |
| Post MI |
0.671 |
BETA |
69.3;34 |
[30] |
| Post stroke |
0.519 |
BETA |
2.7;2.5 |
[30] |
| Post bleed | 0.627 | BETA | 405.6;241.13 | [30] |
*All costs were converted to 2012 Dutch costs using harmonized index of consumer prices (HICP).
‡This cost was obtained from the Financial department of Maastricht University Medical Centre.
†Mode for BETA Pert distribution.