Fig. 1

The course of headache in patients with mild traumatic brain injury is represented by changes in numeric rating scale (NRS) score from onset to 36-month follow-up. Compared with NRS scores at onset, those at 1-month follow-up were significantly decreased. Follow-up NRS scores were significantly lower at 12-, 24-, and 36-month follow-ups compared to 1-month follow-up. The NRS scores decreased continuously until 36-month follow-up. Dots indicate mean NRS scores at each time point and error bars indicate the 95% confidence intervals