Comparison of Responsiveness and Minimal Clinically Important Difference of the Capabilities of Upper Extremity Test (CUE-T) and the Graded Redefined Assessment of Strength, Sensibility and Prehension (GRASSP)

Background: The Capabilities of Upper Extremity Test (CUE-T) and the Graded Redefined Assessment of Strength, Sensibility and Prehension (GRASSP) were both developed to detect change in upper extremity (UE) function in persons with tetraplegia. Objective: To compare the responsiveness and minimal clinically important difference (MCID) of the CUE-T and the quantitative prehension (QtP) scale of the GRASSP. Methods: Subjects included 69 persons with tetraplegia: 60 with acute and 9 with chronic injuries. Subjects were assessed twice 3 months apart using the CUE-T, QtP-GRASSP, and upper extremity motor scores (UEMS). Subjects rated their impression of change in overall and right/left UE function from -7 to +7. The standardized response mean (SRM) was determined for acute subjects. MCID was estimated using a small subjective change (2-3 points) and change in UEMS. Results: Subjects were 41.9 ± 18.1 years old, neurological levels C1-C7; 25 were motor complete. For acute subjects, the SRMs for total/side CUE-T scores were 1.07/0.96, and for the QtP-GRASSP they were 0.88/0.78. MCIDs based on subjective change for total/side CUE-T scores were 11.7/6.1 points and for QtP-GRASSP were 6.4/3.0 points. Based on change in UEMS, MCIDs for total/side were 11.9/6.3 points for CUE-T and 6.0/3.3 points for QtP-GRASSP. Some subjects had changes in the CUE-T due to its arm items that were not seen with the QtP-GRASSP. Conclusion: Both the CUE-T and QtP-GRASSP are responsive to change in persons with acute cervical spinal cord injury with large SRMs. The CUE-T detects some changes in UE function not seen with the QtP-GRASSP.