title: Responsiveness, Sensitivity, and Minimally Detectable Difference of the Graded and Redefined Assessment of Strength, Sensibility, and Prehension, Version 1.0.
abstract: As spinal cord injury (SCI) trials begin to involve subjects with acute cervical SCI, establishing the property of an upper limb outcome measure to detect change over time is critical for its usefulness in clinical trials. The objectives of this study were to define responsiveness, sensitivity, and minimally detectable difference (MDD) of the Graded Redefined Assessment of Strength, Sensibility, and Prehension (GRASSP). An observational, longitudinal study was conducted. International Standards of Neurological Classification of SCI (ISNCSCI), GRASSP, Capabilities of Upper Extremity Questionnaire (CUE-Q), and Spinal Cord Independence Measure (SCIM) were administered 0-10 days, 1, 3, 6, and 12 months post-injury. Standardized Response Means (SRM) for GRASSP and ISNCSCI measures were calculated. Longitudinal construct validity was calculated using Pearson correlation coefficients. Smallest real difference for all subtests was calculated to define the MDD values for all GRASSP subtests. Longitudinal construct validity demonstrated GRASSP and all external measures to be responsive to neurological change for 1 year post-injury. SRM values for the GRASSP subtests ranged from 0.25 to 0.85 units greater than that for ISNCSCI strength and sensation, SCIM-SS, and CUE-Q. MDD values for GRASSP subtests ranged from 2-5 points. GRASSP demonstrates good responsiveness and excellent sensitivity that is superior to ISNCSCI and SCIM III. MDD values are useful in the evaluation of interventions in both clinical and research settings. The responsiveness and sensitivity of GRASSP make it a valuable condition-specific measure in tetraplegia, where changes in upper limb neurological and functional outcomes are essential for evaluating the efficacy of interventions.
authors.affiliation: 1 Department of Physical Therapy, Toronto Western Hospital , Toronto, Ontario, Canada .|6 University of Toronto , Toronto, Ontario, Canada .|7 Krembil Neuroscience Centre, Toronto Western Hospital , Toronto, Ontario, Canada .|8 University Health Network , Department of Neurosurgery, Toronto Western Hospital, Toronto, Ontario, Canada .|11 GRASSP Longitudinal Study Team .
authors.forename: Sukhvinder
authors.initials: S
authors.lastname: Kalsi-Ryan
authors.affiliation: 2 Department of Occupational Therapy, St. Michaels Hospital , Toronto, Ontario, Canada .|3 Rehabilitation Science Institute, St. Michaels Hospital , Toronto, Ontario, Canada .|6 University of Toronto , Toronto, Ontario, Canada .|9 St. Michael's Hospital , Toronto, Ontario, Canada .
authors.forename: Dorcas
authors.initials: D
authors.lastname: Beaton
authors.affiliation: 4 Department of Surgery, St. Michaels Hospital , Toronto, Ontario, Canada .|6 University of Toronto , Toronto, Ontario, Canada .|9 St. Michael's Hospital , Toronto, Ontario, Canada .|11 GRASSP Longitudinal Study Team .
authors.forename: Henry
authors.initials: H
authors.lastname: Ahn
authors.affiliation: 11 GRASSP Longitudinal Study Team .|12 Spinal Cord Injury Research, St. Joseph's Health Care , London, Ontario, Canada .
authors.forename: Heather
authors.initials: H
authors.lastname: Askes
authors.affiliation: 11 GRASSP Longitudinal Study Team .
authors.forename: Brian
authors.initials: B
authors.lastname: Drew
authors.affiliation: 10 Spinal Cord Injury Centre, University Hospital Balgrist , Zurich, Switzerland .|11 GRASSP Longitudinal Study Team .
authors.forename: Armin
authors.initials: A
authors.lastname: Curt
authors.affiliation: 3 Rehabilitation Science Institute, St. Michaels Hospital , Toronto, Ontario, Canada .|5 Institute of Biomaterials and Biomedical Engineering, University of Toronto , Toronto, Ontario, Canada .|6 University of Toronto , Toronto, Ontario, Canada .|8 University Health Network , Department of Neurosurgery, Toronto Western Hospital, Toronto, Ontario, Canada .|11 GRASSP Longitudinal Study Team .
authors.forename: Milos R
authors.initials: MR
authors.lastname: Popovic
authors.affiliation: 7 Krembil Neuroscience Centre, Toronto Western Hospital , Toronto, Ontario, Canada .
authors.forename: Justin
authors.initials: J
authors.lastname: Wang
authors.affiliation: 1 Department of Physical Therapy, Toronto Western Hospital , Toronto, Ontario, Canada .|3 Rehabilitation Science Institute, St. Michaels Hospital , Toronto, Ontario, Canada .|6 University of Toronto , Toronto, Ontario, Canada .|8 University Health Network , Department of Neurosurgery, Toronto Western Hospital, Toronto, Ontario, Canada .|11 GRASSP Longitudinal Study Team .
authors.forename: Mary C
authors.initials: MC
authors.lastname: Verrier
authors.affiliation: 4 Department of Surgery, St. Michaels Hospital , Toronto, Ontario, Canada .|6 University of Toronto , Toronto, Ontario, Canada .|7 Krembil Neuroscience Centre, Toronto Western Hospital , Toronto, Ontario, Canada .|8 University Health Network , Department of Neurosurgery, Toronto Western Hospital, Toronto, Ontario, Canada .|11 GRASSP Longitudinal Study Team .
authors.forename: Michael G
authors.initials: MG
authors.lastname: Fehlings
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care / Q000379:methods* / Q000592:standards; D011594:Psychometrics / Q000295:instrumentation*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013119:Spinal Cord Injuries / Q000628:therapy*; D055815:Young Adult