Table 2 Changes in headache intensity (NPRS) and disability (NDI) with 95 % confidence intervals for both groups and between-group differences

 Baseline: Mean (SD)

6.4 (1.6)

6.0 (2.1)

 1-Week: Mean (SD)

3.1 (1.9)

4.9 (1.8)

 Change Score: Baseline to 1-Week

3.2 (2.6, 3.8)

1.2 (0.6, 1.7)

2.1 (1.2, 2.9); P < 0.001

 4-Week: Mean (SD)

1.8 (1.6)

3.8 (2.0)

 Change Score: Baseline to 4-Week

4.5 (4.0, 5.1)

2.2 (1.7, 2.8)

2.3 (1.5, 3.1); P < 0.001

 3-Month: Mean (SD)

2.0 (1.8)

3.8 (1.9)

 Change Score: Baseline to 3-Month

4.3 (3.7, 4.9)

2.2 (1.6, 2.9)

2.1 (1.2, 3.0); P < 0.001

 Baseline: Mean (SD)

18.1 (7.9)

19.2 (7.8)

 1-Week: Mean (SD)

11.9 (8.5)

16.1 (7.5)

 Change Score: Baseline to 1-Week

6.2 (4.8, 7.6)

3.1 (2.0, 4.1)

3.1 (1.4, 4.9); P < 0.001

 4-Week: Mean (SD)

6.5 (5.4)

13.0 (7.5)

 Change Score: Baseline to 4-Week

11.6 (9.7, 13.4)

6.1 (4.9, 7.4)

5.4 (3.2, 7.7); P < 0.001

 3-Month: Mean (SD)

6.3 (5.9)

13.5 (7.8)

 Change Score: Baseline to 3-Month

11.7 (9.7, 13.8)

5.7 (4.2, 7.2)

6.0 (3.5, 8.6); P < 0.001