A French longitudinal study beginning in childhood FReSH-69765-en Rémy Ben Messaoud A French longitudinal study beginning in childhood ELFE FReSH-69765-en thiery SIMEON INSTITUT NATIONAL DE LA SANTE ET DE LA RECHERCHE MEDICALE (INSERM) France Recherche en Santé Humaine (FReSH) AGENCE NATIONALE DE LA RECHERCHE (ANR) null thriery;SIMEON CNIL CPP socialization pregnancy child Environmental determinants Environmental determinants: Climate Behavioral determinants Behavioral determinants: Addiction null Study of the determinants of development, health, and Socialization of children: Elfe is one of the two constituent cohorts of the RE-CO-NAI platform with the Epipage 2 cohort. The overall objective of The goal of this platform is to establish an infrastructure that provides the systems necessary for the collection, highly secure storage, and the dissemination of data on pregnancy, childbirth, and children. The research platform thus established based on cohorts of children under observation from birth will make it possible to study in a comprehensive manner and a multidisciplinary approach to major issues in health, development, and children's socialization. It will also provide significant visibility in the world of academic research (both in France and internationally), but as well as among organizations, associations, and manufacturers interested in childhood. This will enable optimal use of the data collected and will facilitate the dissemination of the data. A collection of Additional clinical and biological data were collected during the first COVID-19 lockdown as part of the collaborative project between Sapris cohorts France Individus General population Female Male Infant, Newborn (birth to 28 days) Infant (28 days to 2 years) Child, Preschool (2 to 5 years) Child (6 to 12 years) Adolescent (13 to 18 years) Clinical data none Prospective longitudinal none Probability Probability: Stratified Medical-administrative database (patients health insurance/mutual insurance) [10000-20000[ individuals Self-administered questionnaire Observational Study Observational Study Cohort study Other 18,300 Ongoing study Restricted access thiery;SIMEON