The 1998 SLÁN survey was conducted by the Centre for Health Promotion Studies at NUI Galway on behalf of the Health Promotion Unit of the Department of Health. One of the main purposes of the survey was to produce baseline information for the ongoing surveillance of health and lifestyle related behaviours in the Irish adult population. A self-administered questionnaire, an adapted version of the semi- quantitative food frequency questionnaire (SQFFQ) used in the British arm of the European Prospective Investigation of Cancer (EPIC) study (Riboli, 1997) was developed for use in SLAN. The EPIC food frequency instrument has been validated extensively in several populations (Bingham et al., 1997) and used in a survey of diet and lifestyle of Irish women (NNSC, 1998) and validated using food diaries and a protein biomarker in volunteers of the National University of Ireland, Galway (Harrington, 1997 Thesis). There were eight sections in the questionnaire which covered general health (including self-reported height and weight), exercise, tobacco, illegal substances, accidents, household details and dietary habits.

Probability. Multistage. Sampling frame: Electoral Register. Sample: Multistaged sample drawn by electoral division. Stratification: Proportionate distribution across each of the 26 counties, locality and gender

Self-administered questionnaire: Paper