An FFT and FFTT decision trees were informed by IMPROVE risk assessment scores ≥2 (A) and ≥4 (B) and evidence-based ASH guidelines; (C) impact on bleeding and VTE outcomes. The strategy with the lowest weighted average is considered the best. P(D+|T+)− probability of VTE if the test is “positive” that is, IMPROVE score exceeds given score (= PPV); P(D+|T−)− probability of VTE if the test is “negative” that is, IMPROVE Score <given score; TP, true positives; FP, false positive; TN, true negatives; FN, false negatives.