Initiative to reduce inappropriate venous thromboembolism prophylaxis in an 11-hospital safety net system: An electronic health records-based approach.

Compared to the preintervention period, the first intervention did not change the rate of total pharmacologic prophylaxis immediately after implementation (1.7% relative change, p = .38) or over time (slope difference of 0.20 orders per 1000 patient days, p = .08). Compared to the first intervention period, the second intervention led to an immediate 4.5% reduction in total pharmacologic prophylaxis (p = .04) but increased thereafter (slope difference of 0.24, p = .03) such that weekly rates at the end of the study were similar to rates prior to the second intervention.