Headache cessation by an educational intervention in grammar schools: a cluster randomized trial - Albers, L; Heinen, F; Landgraf, M; Straube, A; Blum, B; Filippopulos, F; Lehmann, S; Mansmann, U; Berger, U; Akboga, Y; von Kries, R (Eur J Neurol, 2015)