Additional file 1 of Back pain in children surveyed with weekly text messages - a 2.5 year prospective school cohort study

Additional file 1: Table S1.: Number of children with back pain at least once in a survey year. Table S2. Number of children with back pain at least twice in a survey year. Table S3. Number of girls with back pain at least twice in a survey year. Table S4. Number of boys with back pain at least twice in a survey year. (XLSX 45 KB)