Examining the Construct Validity of Posttraumatic Growth Following Moderate-Severe Traumatic Brain Injury: A Mixed-Methods Analysis

Purpose/Objective: Posttraumatic growth (PTG) refers to positive changes that individuals experience in the wake of a stressful or traumatic event. Though growth and adaptation are considered ideal outcomes of rehabilitation, the extent to which PTG captures the unique experience of individuals with traumatic brain injury (TBI) has not been empirically evaluated. The purpose of the current study was to establish construct validity of PTG for individuals following moderate-severe TBI. Research Method: Forty participants who received inpatient or outpatient rehabilitation services for moderate-severe TBI and who were >1 year postinjury completed a one-time phone interview of mental health and quality of life assessments, and answered a free-response question about significant life changes after injury. Using convergent parallel design, scores on the Posttraumatic Growth Inventory (PTGI) were compared to other assessments and themes of PTG and posttraumatic depreciation derived through thematic analysis. Results: PTGI total scores (M = 66.60, SD = 21.79) were similar to other brain injury populations respective to time since injury (M = 11.20 years). Qualitatively derived themes of PTG aligned with domains of the PTGI, and endorsement of PTG was significantly associated with greater mental health and social support. Discussion: This study provides evidence of the existence of PTG and posttraumatic depreciation in a sample of individuals with moderate-severe TBI, supporting its construct validity using mixed-methods data. Our findings may be helpful in identifying what significant changes may indicate significant growth and depreciation during the rehabilitation process, and be critical mechanisms for optimal psychosocial adjustment following brain injury.