Assessing alexithymia in adults with acquired brain injury: Psychometric properties of the Perth Alexithymia Questionnaire.

Background: Alexithymia is a multidimensional personality trait comprised of difficulty identifying feelings, difficulty describing feelings, and externally orientated thinking. The assessment of alexithymia in people with acquired brain injury (ABI) is of clinical interest because alexithymia is linked to poor psychosocial functioning and community reintegration after ABI. To date, alexithymia measures have not been psychometrically investigated/validated in an ABI sample, restricting confident empirical work in this area. We aimed to fill this gap by assessing the psychometric properties of the Perth Alexithymia Questionnaire (PAQ) in adults with ABI and determining whether the alexithymia construct manifests similarly in ABI samples compared to the general community.

Methods: The PAQ and Depression Anxiety Stress Scales-21 were administered to an ABI sample (N = 350) and a community sample (N = 1012). Factor structure, measurement invariance, internal consistency reliability, and concurrent/discriminant validity were explored.

Results: Our confirmatory factor analysis of the PAQ supported the intended five-factor correlated model as the best solution, where items loaded well onto the five intended subscales. This factor structure was invariant across ABI and community samples. Good reliability and concurrent and discriminant validity were also established.

Limitations: The PAQ is a self-report measure and may be impacted by insight deficits known to occur after ABI.

Conclusion: Our data suggests that the PAQ has good validity and reliability as a measure of alexithymia. The latent structure of alexithymia manifests similarly in ABI and community samples. This study provides the first psychometric foundation for confident assessment of alexithymia in ABI.