Reliability and predictive validity of the bedside upper limb functional evaluation tool (BUFET) among stroke subjects – a psychometric study

The Bedside Upper Limb Functional Evaluation Tool (BUFET) is a newly developed tool that assesses upper extremity functions, including proximal and distal movements such as gestures, gripping, and independent finger movements. This study aimed to evaluate the intra-rater and inter-rater reliability and predictive validity of the BUFET. Subjects ≥ 18 years of age and with a first episode of supratentorial stroke were included. The principal investigator, a physiotherapist, rated the subjects while performing the scale which was videotaped. To establish intra-rater reliability, the same rater re-scored the videos on two separate occasions, after 7 and 30 days. For inter-rater reliability, the principal investigator and 4 additional raters independently scored the patient based on the video. For predictive validity, the Wolf Motor Function Test (WMFT) was administered on the same day as BUFET, followed by administering the scales after 30 days. Intra- and inter-rater reliability was found to be excellent (ICC-0.992, 0.985). The reliability of all the components was > 0.89. The predictive validity was demonstrated by R² values were 0.479 when compared with the WMFT scale. The study concluded that BUFET is an instrument with high intra-rater and inter-rater reliability with moderate predictive validity.