Reliability of the clinical outcome variables scale when administered via telephone to assess mobility in people with spinal cord injury

Objective: To examine the equivalence reliability and testretest reliability of the Clinical Outcome Variables Scale (COVS) when administered via telephone (TCOVS) to people with spinal cord injury (SCI). Design: Equivalence (telephone administration vs in-person) and test-retest reliability study. Setting: Assessments conducted in participants' home environment. Participants: Equivalence reliability was examined in a convenience sample of 37 people with a diagnosis of traumatic SCI who had been discharged from the Queensland Spinal Injuries Unit to the community. In a separate group of participants, testretest reliability of COVS when administered via telephone was examined in 43 people with SCI who were randomly selected from the Queensland Spinal Cord Injuries Service records. Interventions: Not applicable. Main Outcome Measures: Reliability was assessed at the subscale and composite score level using intraclass correlation coefficients (ICC2.1) and Bland-Altman limits of agreement. Results: Reliability was good for TCOVS and COVS for the composite score (ICC=.98), mobility subscale (ICC=.97), and ambulation subscale (ICC=.99). Reliability was also good for TCOVS test and retest assessments for the composite score (ICC= 1), mobility subscale (ICC= 1), and ambulation subscale (ICC= 1). For all comparisons, most data points were within the 95% limits of agreement and the width of limits of agreement were considered to be clinically acceptable. Conclusions: The study findings confirm the equivalence and test-retest reliability of the TCOVS in an SCI population when administered by trained raters