We validated a German-language self-administered headache questionnaire for migraine (M), tension-type headache (TTH) and trigeminal autonomic cephalalgia (TAC) in a general population sample of people with headache. Randomly selected subjects (n = 240) diagnosed by the questionnaire as M (n = 60), TTH (n = 60), a combination of M and TTH (M+TTH, n = 60) and TAC (n = 60) were invited for examination by headache specialists. One hundred and ninety-three subjects (80%) were studied. Sensitivity and specificity for M were 0.85 and 0.85, for TTH 0.6 and 0.88, for M+TTH 0.82 and 0.87, respectively. Cohen's kappa was 0.6 (95% confidence interval 0.50, 0.71). Of 45 patients with TAC according to the questionnaire, physicians diagnosed cluster headache in two patients only. We conclude: (i) the questionnaire can be used to diagnose M, TTH and M+TTH, but not TAC; (ii) screening questionnaires for epidemiological research should be validated in a general population sample but not in a tertiary headache clinic.