Long-term factor structure of the Rivermead Post-Concussion Symptom Questionnaire in mild traumatic brain injury and normative sample

Abstract

Background: Previous studies of the Rivermead Post-Concussive Questionnaire(RPQ)'s factor structure were conducted within 1 year post-injury. Post-concussive symptoms may persist, and are common in the general population, so determining if the factor structure in mild-TBI and controls differ is important. This study examined factor structure of the RPQ in adults 4 years post-mild-TBI and in age-/gender-matched controls.

Method: A total of 232 adults 4 years post-mild-TBI and 232 age-/gender-matched controls completed the RPQ.

Results: Both samples produced a three-factor solution (57.98% and 56.44% of variance in the RPQ). Factor 1 for both samples included all RPQ items and accounted for the majority of variance explained (42.6% and 40.7%). After mild-TBI factor 2 included dizziness, vomiting/nausea, irritability, and double vision; whilst in controls it involved headache, dizziness, vomiting/nausea, and slowed thinking. Factor 3 for mild-TBI included vomiting/nausea, blurred vision, slowed thinking, and poor memory; while for controls it was restricted to visual symptoms (blurred vision, light sensitivity, double vision).

Conclusion: The RPQ factor structure was similar for both groups, although differences were identified in lesser factors. This suggests those with mild-TBI differ minimally from matched controls in the very long term after injury.

Keywords: Factor structure; Post concussion; Rivermead Post Concussion Symptom questionnaire.