Table 2.

Crude (observed) prevalences of all headache and each headache type, overall and according to demographic variables, and gender- and age-adjusted prevalences (N = 2505)

	All headache (n = 1858)	Migraine (n = 519)	TTH (n = 605)	pMOH (n = 18)	Other headache on ≥ 15 d/m (n = 73)	UdH (n = 601)
Observed prevalences (% [95% CI])
Overall	74.2 [72.5–75.9]	20.7 [19.1–22.3]	24.2 [22.5–25.9]	0.7 [0.4–1.0]	2.9 [2.2–3.6]	24.0 [22.3–25.7]
Gender
male (n = 1169)	67.8 [65.1–70.5]	18.6 [16.4–20.8]	22.3 [19.9–24.7]	0.2 [0.0–0.5]	1.5 [0.8–2.2]	24.0 [21.7–26.3]
female (n = 1336)	79.7 [77.5–81.9]	22.5 [20.3–24.7]	25.8 [23.5–28.1]	1.2 [0.6–1.8]	4.2 [3.1–5.3]	24.0 [21.6–26.5]
Age group (years)
7–11 (n = 1382)	62.7 [60.2–65.2]	17.9 [15.9–19.9]	17.5 [15.5–19.5]	0.3 [0.0–0.6]	1.3 [0.7–1.9]	23.8 [21.6–26.1]
12–17 (n = 1123)	88.3 [86.4–90.2]	24.2 [21.7–26.7]	32.3 [29.6–35.0]	1.3 [0.6–2.0]	4.9 [3.6–6.2]	24.2 [21.7–26.7]
School income category*
high (n = 1828)	75.6 [73.6–77.6]	21.8 [19.9–23.7]	25.7 [23.7–27.7]	0.7 [0.3–1.1]	3.1 [2.3–3.9]	22.5 [20.6–24.4]
middle (n = 168)	61.9 [54.6–69.2]	20.8 [14.7–26.9]	16.1 [10.5–21.7]	0.6 [0.0–1.8]	1.2 [0.0–2.8]	22.0 [15.7–28.3]
low (n = 509)	73.1 [69.2–77.0]	16.9 [13.6–20.2]	21.4 [17.8–25.0]	0.8 [0.0–1.6]	2.9 [1.4–4.4]	29.9 [25.9–33.9]
School locality
urban (n = 1660)	73.3 [71.2–75.4]	21.6 [19.6–23.6]	24.8 [22.7–26.9]	0.7 [0.3–1.1]	2.5 [1.7–3.3]	22.0 [20.0–24.0]
semi-rural (n = 336)	79.5 [75.2–83.8]	22.3 [17.8–26.8]	25.3 [20.7–29.9]	0.9 [0.0–1.9]	4.8 [2.5–7.1]	24.7 [20.1–29.3]
rural (n = 509)	73.1 [69.2–77.0]	16.9 [13.6–20.2]	21.4 [17.8–25.0]	0.8 [0.0–1.6]	2.9 [1.4–4.4]	29.9 [25.9–33.9]
Gender and age-adjusted prevalences (% [95% CI])
Overall	76.6 [74.9–78.3]	21.4 [19.8–23.0]	25.6 [23.9–27.3]	0.8 [0.5–1.2]	3.1 [2.4–3.8]	24.0 [22.3–25.7]

TTH tension-type headache, pMOH probable medication-overuse headache, d/m days/month, UdH undifferentiated headache, CI confidence interval; * see text or Table 1 for explanation. Tables 3 and 4 provide odds ratios and adjusted odds ratios for these comparisons