They have been shown to be valid , reliable , and responsive , with a low administration burden .
BACKGROUND The aim of this study was to perform a st and ardized and systematic evaluation of the available evidence on multi-item shoulder-specific patient-reported outcome measures that are applicable to a wide spectrum of disorders .
Development and Psychometric Evaluation of the Flexilevel Scale of Shoulder Function
Background . Existing measures of self‐reported shoulder function fail to measure effectively the full range of shoulder functioning . The classic approach for improving the reliability of a scale is adding items , but a scale with a substantial number of items imposes a large response burden on participants . A more efficient approach is to use modern psychometric methods to construct an adaptive scale in which patients respond only to items that are targeted at their level of shoulder function . Objectives . We developed a Flexilevel Scale of Shoulder Function ( FLEX‐SF ) . This scale includes three testlets that target low , medium , and high shoulder function . Scores on the testlets were equated to a common mathematical metric . Design and Subjects . We developed an initial pool of 68 items . This pool was administered to 400 patients , and responses were calibrated using a rating scale model . Subsets of items were identified for an easy , medium difficulty , and hard testlet . Properties of the scale were evaluated in a 3‐month longitudinal study of 200 shoulder patients . Results . The FLEX‐SF exhibited high reliability at both the scale level ( intraclass correlation coefficient [ 3,1 ] = 0.90 ) and specific trait levels . The validity of the FLEX‐SF was supported by its internal and external responsiveness ( Guyatt responsiveness index = 1.12 ) and the pattern of its associations with other health status measures . Conclusions . The FLEX‐SF can be used as a primary endpoint in clinical trials even when there are relatively few people in each treatment group . The scale also has excellent properties for use in clinical setting s tracking individual changes over time
They have been shown to be valid , reliable , and responsive , with a low administration burden .
BACKGROUND The aim of this study was to perform a st and ardized and systematic evaluation of the available evidence on multi-item shoulder-specific patient-reported outcome measures that are applicable to a wide spectrum of disorders .