Padua prediction score or clinical judgment for decision making on antithrombotic prophylaxis: a quasi-randomized controlled trial

The Padua prediction score (PPS) has been suggested as the best available model for the assessment of the risk of venous thromboembolism (VTE) in hospitalized medical patients. The impact of its use in clinical practice has never been prospectively evaluated. According to a quasi-randomized study design, consecutive patients admitted to Internal Medicine Section 1 were allocated to a PPS-based decisional strategy suggesting thromboprophylaxis in patients with PPS score ≥4, and those admitted to Section 2 to a clinical judgment-based strategy. Study patients underwent complete compression ultrasonography of the lower limbs at discharge. The primary outcome was symptomatic or asymptomatic VTE during hospital stay. Secondary outcomes were VTE excluding isolated distal deep vein thrombosis, bleedings, and appropriate thromboprophylaxis. 628 patients were included in the analysis, 235 in the PPS group, and 393 in the clinical judgment group. The two groups differed for length of hospital stay, prevalence of recent trauma or surgery, and stroke. Compared with control, the PPS group had a significantly lower incidence of VTE (8.5 vs. 15.5 %, OR 0.51, 95 % CI 0.30–0.86), also after adjusting for thromboprophylaxis use and patient PPS-risk category (OR 0.54, 95 % CI 0.31–0.94). In conclusion, the use of PPS was associated with a higher rate of appropriate thromboprophylaxis prescription; no significant differences were found in the other secondary outcomes. The use of PPS for the assessment of risk for VTE is associated with a reduced incidence of VTE compared with the clinical judgment. These result needs to be confirmed in future studies.