Reliability and validity of the revised transfer assessment instrument

Background: Proper transfer technique is associated with improved biomechanics and decreased pain and pathology. However, many users do not use proper technique, and appropriate assessment and training are needed to address these deficits. The transfer assessment instrument (TAI) 4.0 was designed to meet those needs and improve on past versions by removing the need for clinician training, shortening administration time, and simplifying question content. Objectives: Evaluate the psychometric properties of the TAI 4.0. Methods: A convenience sample of full-time wheelchair users was scored on multiple transfers by four raters to assess interrater, intrarater, and test-retest reliability and concurrent validity of the TAI 4.0. Each user also was scored using a visual analog scale (VAS). Results: For 44 participants, the mean TAI 4.0 and VAS across all transfers were 7.58 ± 1.12 and 7.44 ± 1.78, respectively, and scores were significantly correlated (r = 0.52-0.7). VAS scores were more strongly influenced by the flight/landing and body setup phases of the transfer. There were no significant associations between TAI 4.0 score and demographics. Intraclass correlation coefficients (ICC) ranged from 0.80 to 0.85 for interrater reliability, 0.60 to 0.76 for intrarater reliability, and 0.55 to 0.76 for test-retest reliability. The minimum detectable change (MDC) for the total score ranged from 1.02 to 1.30. Conclusion: The TAI 4.0 provides reliable and valid quantitative assessment of an individual's transfer without the need for comprehensive training, as is the case with the TAI 3.0. The tool can be completed in 3 minutes (average) in a clinical setting with only a ruler and goniometer.