Purpose: The clinical effectiveness of a group-visit model versus individual point-of-care visits is compared by International Normalized Ratio (INR) monitoring in a pharmacist-managed anticoagulation clinic.
Methods: This study was a prospective, randomized, repeated-measures, two-group, intention-to-treat comparison and survey at a pharmacist-managed anticoagulation clinic in a managed-care ambulatory care setting. Patients were eligible for this study if they were taking warfarin therapy for at least 30 days, had a goal INR range, and provided consent. At a routine point-of-care visit, eligible patients were randomly invited to participate in group visits. The number of visits and INR values were documented prospectively for both groups during the 16-week study period.
Results: Of the 45 patients who consented and enrolled in group visits, 28 patients participated for the 16-week study period. The control group included 108 patients seen by a pharmacist for individual anticoagulation appointments. No significant difference in the percentage of INR values within the therapeutic range was detected between patients in the group-visit model versus patients receiving individual visits (59% versus 56.6%, respectively; p = 0.536). Seventy-three percent of INR values for patients who attended group visits were within +/- 0.2 of the desired INR range compared with 71.9% of those in the control group ( p = 0.994). In addition, 79% of group-visit patients were within the therapeutic range at their last clinic visit compared with 67% of patients who attended individual appointments (p = 0.225). Group visits were preferred by 51% (n = 38) of patients who completed the satisfaction survey. Of the 92 patients who declined group-visit participation, 36% indicated that the time of day that group visits were offered was inconvenient. There were no thromboembolic or hemorrhagic events documented in either group during the study period.
Conclusion: Group visits in a pharmacist-managed anticoagulation clinic may provide a safe and effective alternative to individual appointments.