Use of the Barthel Index and Modified Rankin Scale in acute stroke trials

Background and Purpose-The Barthel Index (BI) and the Modified Rankin Scale (MRS) are commonly used scales that: measure disability or dependence in a ctivities of daily living in stroke victims. The objective of this study wa s to investigate how these scales were used and interpreted in acute stroke trials. Methods-We identified from MEDLINE the major efficacy trials with neuroprot ective drugs, thrombolytic drugs, and anticoagulants in acute ischemic stro ke published between January 1995 and December 1998. We selected those tria ls that used the BI and/or MRS as outcome parameters. Results-Fifteen trials fulfilling the inclusion criteria were identified. T he BI was used in 13 and the MRS in 8. In 4 trials mean and median scores o f the BI were used, and in I trial median scores of the MRS were compared. Primary end points included the BI in 7, the MRS in 6, and both the BI and MRS in 3. With regard to the BI, a variety of sum scores between 50 and 95 were used as cutoff scores to define favorable outcome. Favorable outcome o n the MRS was defined as either less than or equal to 1 or less than or equ al to 2. Conclusions-Among the efficacy trials in acute stroke,we found remarkable d ifferences in the choice of primary end points and in the definition of fav orable outcome on both the BI and MRS. This lack of consensus strongly hind ers the design, interpretation, and comparison of acute stroke trials. In g eneral, it may be easier to define poor outcome instead of favorable outcom e. Poor outcome could be defined if any of the following end points are rea ched: death, institutionalization due to stroke, MRS >3, or BI <60.