Fig. 6

Long-term effect of onabotulinumtoxinA by country. a) Number of headache days per 28-d period and b) change in number of headache days vs baseline, depicting the outcomes after 5 (wk 60) and 9 (wk 180) treatments. *P < 0.001; paired t-test used to compare visit to baseline. †P-value for comparing among subgroups is from one-way analysis of variance