  Obesity is a complex disease and its prevalence depends on multiple factors
related to the local socioeconomic, cultural and urban context of individuals.
Many obesity prevention strategies and policies, however, are horizontal
measures that do not depend on context-specific evidence. In this paper we
present an overview of BigO (http://bigoprogram.eu), a system designed to
collect objective behavioral data from children and adolescent populations as
well as their environment in order to support public health authorities in
formulating effective, context-specific policies and interventions addressing
childhood obesity. We present an overview of the data acquisition, indicator
extraction, data exploration and analysis components of the BigO system, as
well as an account of its preliminary pilot application in 33 schools and 2
clinics in four European countries, involving over 4,200 participants.
