A mixed methods study to develop an instrument to assess family quality of life among caregivers of adults with traumatic brain injury

Purpose: Traumatic brain injury (TBI) is a major public health problem. It is the leading cause of disability and death among young adults and children globally. Family members often assume the primary caregiving role for the member with TBI; this responsibility may lead to less than ideal family outcomes. The purpose of this mixed methods study was to develop a valid and reliable survey instrument to assess hypothesized domains of Family Quality of Life (FQOL) among caregivers of adults with moderate-severe TBI.;Method: The first phase critically assessed literature on family-level outcome measures for families with a member with TBI. Findings were used to develop a draft survey instrument to assess FQOL among caregivers of adults with moderate-severe TBI. Collecting quantitative and qualitative data from 16 TBI rehabilitation content experts during the second phase enabled the researcher to develop a content valid instrument. The third phase qualitatively pre-tested the instrument by conducting cognitive interviews (think-alouds and verbal probing) with eight purposefully selected caregivers of adults with moderate-severe TBI. The fourth phase quantitatively examined the psychometric properties (construct validity and internal consistency reliability) of the instrument by collecting data from 95 caregivers of adults with moderate-severe TBI.;Analysis/Results: The systematic review of literature resulted in a draft instrument. The second phase of the study yielded a revised instrument with five hypothesized domains of FQOL. Content experts guided selection of a five-point Likert-type response scale to measure items. In the third phase, theme(s) emerged during caregiver cognitive interviews for each hypothesized domain of FQOL; data guided development of additional items about caregiver problem solving. In the final phase, exploratory factor analysis revealed a four-factor solution. Internal consistency reliability estimates shaped the final instrument which included a 10-item Family Supports factor (alpha .946), 19-item Family Relationships factor (alpha .961), 8-item Family Physical/Material Well-Being factor (alpha 892), and 6-item Head Injury Services factor (alpha .890). The Cronbach's alpha for the 43-item instrument was .972.;Conclusions: The researcher applied a sequential four-phase mixed methods research design to develop the TBI-FQOL Instrument. Statistical results indicate the instrument has a moderate-high level of construct validity and internal consistency reliability.