Table 1 Characteristics of the 60 participants related to examination methods at follow-up

Number (n = 60)

16

24

10

10

Women (%)

44

71

60

70

0.34*

Change in headache days/month at month 5 versus baseline

−1.4

−4.6

−3.3

−9.3

0.22^†

Change in headache index/month at month 5 versus baseline

3.4

−44.4

−42.0

−92.9

0.79^†

Tried less than two preventive drugs at baseline (%)

63

67

70

90

0.48*

Mean number of years from baseline to end of follow-up (95% CI)

4.2 (3.9–4.5)

4.0 (3.9–4.1)

3.5 (2.5–4.5)

0.8 (0.4–1.1)

p < 0.001^†