"Mother-child cohorts are currently collecting a wealth of information on childhood diseases and their determinants across Europe, but these data are often of fragmented nature and there is little coordination to structure and consolidate scattered research. Although cohort research carries large potential policy implications, messages are not always filtering through to policy at the national, let alone the European, level. CHICOS aims to improve child health across Europe by developing an integrated strategy for mother-child cohort research. This will be achieved through the coordination of the most important European cohorts. The project will 1) make an overview of all mother-child cohorts in Europe; 2) evaluate existing information on outcomes and determinants from these cohorts, evaluate links between cohorts and routine registers, identify gaps in knowledge, and develop recommendations for research action at European level for the next 15 years focusing on key areas of policy concern; 3) review the extent to which mother-child cohorts and registries have contributed to current European child health policies and make recommendations to improve the contribution of mother-child cohort research to policy at the European level; and 4) disseminate results of the project to stakeholders and evaluate new technologies for cohort research dissemination. CHICOS is structured along key child health outcome themes (perinatal outcomes, asthma, obesity, cognitive and behavioural development, injuries, infections, childhood cancer) and key determinant themes (social inequalities, nutrition and exercise, lifestyle exposures, environmental toxin exposures, genetic factors and biobanks, multiple risk factors) where European cohorts can and should work together towards a more solid evidence base, which can be used by policy makers. CHICOS will work closely with policy makers to ensure that guidelines across Europe in these areas are based on the best available evidence."