The reliability and validity of the TBI-CareQOL system in four diverse caregiver groups

Purpose Establishing the psychometric reliability and validity of new measures is an ongoing process. More work is needed in to confirm the clinical utility of the TBI-CareQOL measurement development system in both an independent cohort of caregivers of traumatic brain injury (TBI), as well as in additional caregiver groups. Methods An independent cohort of caregivers of people with TBI (n = 139), as well as three new diverse caregiver cohorts (n = 19 caregivers of persons with spinal cord injury, n = 21 caregivers for persons with Huntington disease, and n = 30 caregivers for persons with cancer), completed 11 TBI-CareQOL measures (caregiver strain; caregiver-specific anxiety; anxiety; depression; anger; self-efficacy; positive affect and well-being; perceived stress; satisfaction with social roles and activities; fatigue; sleep-related impairment), as well as two additional measures to examine convergent and discriminant validity (PROMIS Global Health; the Caregiver Appraisal Scale). Results Findings support the internal consistency reliability (all alphas > 0.70 with the vast majority being > 0.80 across the different cohorts) of the TBI-CareQOL measures. All measures were free of ceiling effects, and the vast majority were also free of floor effects. Convergent validity was supported by moderate to high correlations between the TBI-CareQOL and related measures, while discriminant validity was supported by low correlations between the TBI-CareQOL measures and unrelated constructs. Conclusion Findings indicate that the TBI-CareQOL measures have clinical utility in caregivers of people with TBI, as well as in other caregiver groups. As such, these measures should be considered as important outcome measures for clinical trials aiming to improve caregiver outcomes.