Base rate of post-concussion symptoms among normal people and its neuropsychological correlates

Objective: To explore the base rate of symptoms similar to those of post-co ncussion symptoms (PCS) among a group of participants without head injury. The effect of subjective complaints upon cognitive functioning was also exa mined. Design: A cross-sectional study. Participants: A total of 85 participants without head injury, other identif iable neurological diseases or psychiatric diseases were recruited. Outcome measures: These included Rivermead Post-concussion Symptoms Checkli st, Cognitive Failures Questionnaire, Colour Trails Test, Stroop Word-Colou r Test, Paced Auditory Serial Addition Test, Symbol Digits Modality Test, W ord Fluency Test, Design Fluency Test, Digits Forward and Backward Span Tes t, and Modified Six Elements Test. Results: A relatively high proportion of the participants reported symptoms similar to those of patients with PCS. These included longer time to think (65.9%), forgetfulness (58.9%), poor concentration (58.9%), fatigue easily (53.5%), and sleep disturbances (50.6%). Gender effect was not significant for either the individual item or the total score of the Rivermead Post-co ncussion Symptoms Checklist. Moreover, there was no difference found betwee n low symptom reporters and high symptom reporters in terms of attention, w orking memory, mental fluency, and strategy allocation. Conclusion: The base rates of symptoms were consistent with previous studie s among the nonclinical groups. However, persons reporting a high score of concussion-like symptoms did not perform less well than those reporting a l ow score of symptoms in attention, working memory, mental fluency and strat egy allocation.