The aims of this study were to prospectively follow up population-based cohorts of children with widespread pain, children with neck pain and pain-free children, in order to evaluate 1-y changes in pain symptoms and to evaluate predictors for persistent widespread pain and for the change of neck pain to widespread pain. A structured pain questionnaire, the Children's Depression Inventory, and a sleep questionnaire were completed by the pre-adolescent cohorts, and clinical evaluation with tender point palpation and pain threshold measurements was carried out in both years. The Child Behavior Checklist, the Teacher's Report Form and a sociodemographic questionnaire were completed at baseline. More children in the 2 pain cohorts reported pain at follow-up than did controls (p < 0.0001). Children with persistent widespread pain had lower pain thresholds compared with those whose pain classification changed. In the neck pain group, 19 (20.4%) reported widespread pain at follow-up. Although depressive symptoms and sleep problems were associated with the change of neck pain to widespread pain, neither they nor other measured factors showed independent explanatory power in multiple logistic regression analysis. In conclusion, fluctuation of pain symptoms occurred mainly among pain cohorts. Depressive and sleep problems may have an effect on the spreading of regional neck pain to widespread pain. Pain threshold measurement and evaluation of depressive and sleep problems may be useful tools for secondary prevention of musculoskeletal pain in pre-adolescents.