Table 1.
Probabilities used in the decision analysis
| Variables | Baseline probability | Range of plausible probabilities | Threshold value within published range | Threshold from 0 to 1 |
|---|---|---|---|---|
| Probability of DVT | 0.32 [12] | 0.18 to 0.50 [[9] to [11,12]] | No | Yes (> 0.6*) |
| Probability of PE following development of DVT | 0.1[42,43] | 0.01 to 0.18 [22,24,44,45] | No | Yes (> 0.3*) |
| Probability of death from PE | 0.17 [46] | 0 to 0.50 [47] | No | No |
| Probability of a CNS bleed on LMWH | 0.108 [15] | 0.03 to 0.23 [24,44] | No | Yes (> 0.017+) |
| Effectiveness of LMWH in preventing DVT (e) | 0.47 [12] | 0.33 to 0.82 [12,42] | Yes (> 0.8*) | Yes (> 0.8*) |
| Probability of death from a CNS bleed | 0.105 [48] | 0.08 to 0.3 [49,50] | No | No |
| Probability of disabling neurological deficit after CNS bleed | 0.17 [51] | 0.16 to 0.33 [52,53] | No | No |
| Probability of an ICU-related systemic bleed | 0.035 [23] | 0.027 to 0.046 [23] | No | No |
| Probability of death from ICU-related systemic bleed | 0.02 [23] | 0.001 to 0.035 [23,46] | No | No |
| Effectiveness of not receiving LMWH in reducing CNS bleeds | 0.315 [4,15] | 0.001-0.99 [4-6,23,47,54] | Yes (> 0.05+) | Yes (> 0.05+) |
| Effectiveness of not receiving LMWH in reducing ICU-related systemic bleeds | 0.146 | 0 to 0.66 [8,12,55] | No | No |
Table of probabilities and plausible ranges used for the decision analysis. The last two columns indicate variables for which a threshold value was identified in one-way sensitivity analysis. Values with an asterisk (*) indicate a threshold value above which providing anticoagulant prophylaxis becomes the preferred strategy. Values with a plus (+) indicate a threshold value above which withholding anticoagulant prophylaxis becomes the preferred strategy.
CNS: central nervous system; DVT: deep vein thrombosis; ICU: intensive care unit; PE: pulmonary embolism