ENCAT is a regional
survey carried out periodically by the Department of
Health of the Catalan Government and co-ordinated by
the Centre for Research on Community Nutrition of the
University of Barcelona. The theoretical random sample
population and sample size have been described elsewhere15,19,
comprising the population source of residents
in the official census. The samples were stratified
according to household and randomised into subgroupings
with municipalities being the primary sample
units, and individuals within these municipalities comprising
the final sample units.