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An epidemiological study was carried out among schoolchildren from three “forms” (grades) corresponding to ages 8 to 9 years, 12 to 13 years, and 15 to 16 years, respectively. Two representative samples, totaling 4,835, were extracted from the children, who completed the questionnaires in the urban district of Wupperlal and the adjacent, more rural area of Mettmann in Germany. The prevalence of headache...
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