Improving Anticoagulation Measurement: Novel XXXX Composite Measure.

@entity1 @entity64 @entity548 @entity955 @entity1229 @entity385
BACKGROUND: Percent time in therapeutic range (TTR) and international normalized ratio (INR) variability both measure @entity1229 control and are associated with outcomes independently. Here, we examine the advantages of a @entity1229 composite measure (WCM), which summarizes the 2 when measuring @entity1 outcomes. We also examine how the measure chosen would affect anticoagulation clinic performance rankings. METHODS AND RESULTS: We constructed WCM using an equally weighted method, adding standardized TTR to standardized log-transformed INR variability using 103 897 @entity1229 -experienced @entity1 from 100 anticoagulation clinics. We examined the association of WCM with @entity385 , major @entity548 , and fatal @entity548 , using a subset of @entity1 with @entity955 (n=40 404). We divided @entity1 into quintiles based on their level of control for TTR, log INR variability, and WCM. We calculated the hazard ratios for @entity385 , major @entity548 , and fatal @entity548 stratified by these quintiles. WCM hazard ratios' for @entity64 and fatal @entity548 showed the largest difference between excellent control and poorest control quintile compared with TTR and log INR variability, but not for major @entity548 . In addition, we compared site rankings obtained using each of our 3 performance measures. Kappa scores for identifying outlier and nonoutlier clinics between WCM and its components were moderate (k=0.56 for TTR and k=0.62 for log INR variability) but was weak between TTR and log INR variability (k=0.13). CONCLUSIONS: WCM produces the largest range of risk for @entity1229 complications, widening the floor ceiling effects that limit the use of TTR and INR variability as separate measures. Anticoagulation clinics ranking changed considerably according to the anticoagulation measure that was selected.
