Table 1.

Characteristics of participants that took part in the study.

Participant	Age	Sex	HITa disability score at entry
1	46	F	66
2	54	M	80
3	30	F	78
4	61	F	72
5	33	F	64
6	51	M	66
7	56	F	64
8	50	F	74

HIT = headache impact test.

^aHIT reflects the impact of headache on daily activities with a score of over 56 indicating a ‘substantial impact’ (range = 36–84).