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

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.