| Parameter | Value (range) | Source |
| Patient distribution according to VTE risk profile (both branches) | Data from surgical patients from previous audit16 | |
| Low | 0.07 | |
| Moderate | 0.55 | |
| High | 0.18 | |
| Very high | 0.20 | |
| Probability of receiving prophylaxis (before GL implementation) | Data from surgical patients from previous audit16 | |
| Low | 0.22 | |
| Moderate | 0.54 | |
| High | 0.89 | |
| Very high | 0.56 | |
| Probability of receiving prophylaxis (after GL implementation) | Data from surgical patients from previous audit16 | |
| Low | 0.63 | |
| Moderate | 0.73 | |
| High | 0.95 | |
| Very high | 1 | |
| Mean length of prophylaxis | 8 days | GL recommendations18 |
| Outcome probabilities (without prophylaxis)* | ||
| Fatal PE | Mean values (range)8 | |
| Low | 0.0001 | |
| Moderate | 0.0025 (0.001 to 0.004) | |
| High | 0.007 (0.004 to 0.01) | |
| Very high | 0.025 (0.002 to 0.05) | |
| Clinical PE (a) | Mean values (range)8 | |
| Low | 0.002 (0.001 to 0.003) | |
| Moderate | 0.015 (0.01 to 0.02) | |
| High | 0.03 (0.02 to 0.04) | |
| Very high | 0.07 (0.04 to 0.1) | |
| Total DVT (symptomatic and asymptomatic) (b) | Mean values (range)8 | |
| Low | 0.024 (0.02 to 0.03) | |
| Moderate | 0.18 (0.12 to 0.24) | |
| High | 0.36 (0.24 to 0.48) | |
| Very high | 0.75 (0.50 to 0.85) | |
| Major bleeding | 0.02 (0.015 to 0.04) | Muntz et al19 |
| Symptomatic VTE | (a)+[(b)/5] | Hypothesis based on literature8 |
| Asymptomatic VTE | (b)/5×4 | Hypothesis based on literature8 |
| Cost of prophylaxis with heparin (per day) | €0.33 | Hospital figures |
| Cost of elastic stockings (pair) | €5.55 | Hospital figures |
| Cost associated with outcomes | ||
| Major bleeding | €1881.71 | Drg 453 (med.) and 443 (surg.) reimbursement, weighted according to frequency of re-intervention reported in Muntz et al19 |
| Symptomatic VTE | €2639.36 | Drg 128 (DVT) and 78 (PE) reimbursement, weighted approximately according to values from Geerts et al8 |
| Asymptomatic VTE | 0 | Hypothesis20 |
| Fatal PE | €3937.00 | Drg 78 (PE) reimbursement |
*With prophylaxis, outcome probabilities were reduced by 50% according to a hypothesis based on the literature.78
DVT, deep vein thrombosis; GL, clinical guidelines; PE, pulmonary embolism; VTE, venous thromboembolism.