Comparison of the proportion of subjects with (“improved”*) or without (“not improved” ‡) reduction in pain frequency or drug consumption of ≥50% at the end of follow-up (responder rates), between IG and control group.

*“Improved”: subjects with a baseline frequency of ≥4 days/month with pain (or drug consumption) that had a reduction in pain frequency or drug consumption of ≥50% at the end of follow-up.‡“Not improved”: includes subjects with ≥4 days/month with pain (or drug consumption) at the baseline with less than 50% of reduction in pain frequency or drug consumption at the end of follow-up, and those subjects that had a baseline frequency of less than 4 days with pain/drug consumption independently from their results.§adjusted by age, sex, neck/shoulder pain (when analyzing headache and analgesic drug consumption), headache (when analyzing neck/shoulder pain and analgesic drug consumption), education level, job activity and baseline value of each subject.