Community impact of anticoagulation services: Rationale and design of the Managing Anticoagulation Services Trial (MAST)

We describe the design of the Managing Anticoagulation Services Trial (MAST ), a practice-improvement trial testing whether anticoagulation services ar e a preferred method of managing anticoagulation for stroke prevention amon g patients with atrial fibrillation. Most randomized trials within the heal th care environment are designed as efficacy studies to determine what work s under ideal conditions or ideal clinical practice. In contrast, effective ness trials seek to generalize the results of efficacy studies by determini ng what works under more typical practice conditions. Practice-improvement trials are effectiveness trials that examine the management of a clinical p roblem in the context in which care is usually given. Noteworthy features o f the MAST include defining the intervention in functional terms and collab oration with managed care organizations.