Table 4.

 Number of interviews by headache subtypes across 30 years

Headache subtypes across 30 years	No (%) of interviews with same headache				Total No
	1	2	3	≥4
Migraine with or without aura*	93 (49.3)	44 (15.6)	36 (14.6)	47 (20.5)	220
Migraine with aura†	17 (61.8)	5 (19.7)	3 (17.2)	1(1.3)	26
Tension-type headache‡	130 (55.3)	65 (23.0)	32 (14.7)	17 (7.0)	244

*Respondents with ≥4 interviews who had migraine with or without aura at ≥1 interview (n=220).

†Respondents with ≥4 interviews who had migraine with aura at ≥1 interview (n=26).

‡Respondents with ≥4 interviews who had tension-type headache at ≥1 interview (n=244).