Reliability and minimal detectable change of the Trunk Assessment Scale for Spinal Cord Injury (TASS) and the trunk control test for individuals with spinal cord injury.

Study

Design: Cross-sectional study.

Objectives: To evaluate the reliability and calculate the measurement error of the Trunk Assessment Scale for Spinal Cord Injury (TASS) and trunk control test (TCT-SCI) in individuals with spinal cord injury (SCI). Setting: Rehabilitation Hospital in Japan.

Methods: The evaluations of TASS and TCT-SCI for individuals with SCI were video-recorded. The inter-rater reliability (two physiotherapists) was confirmed using the videos. ICC (2,1), kappa coefficient (κ) were used to determine the reliability of the total score and each item. Each minimal detectable change (MDC) was calculated.

Results: The TASS and TCT-SCI total scores showed excellent inter-rater reliability (ICC = 0.99, and 1.00). The kappa coefficients of TASS were acceptable to excellent for 8 items (κ = 0.76-1.00), below acceptable for 1 item (κ = 0.62). The kappa coefficients of TCT-SCI were excellent for 12 items (κ = 0.83-1.00), below acceptable for 1 item (κ = 0.68). The inter-rater MDC of the TASS total score was 4.07 points, and the MDC of the TCT-SCI total score was 1.13 points. The intra-rater MDC of the TASS total score was 3.86 points.

Conclusion: Both TASS and TCT-SCI showed high reliability. Differences of less than four points in TASS and one point in TCT-SCI were interpreted as measurement errors between the two raters.