Once the collection of baseline data is complete, it is important to establish what happens to the participant at a later date. The follow-up of participants employed several different methods.

Self reported questionnaires (eighteen months)
Everyone who consented to join the study was approached eighteen months later. They were sent an information sheet containing a description of EPIC, Europe wide, and a progress report. They were asked to complete a second seven-day food diary and a follow-up health questionnaire. The eighteen-month gap between diaries was selected to ensure that seasonal variations in diet were recorded. If participants responded to this, they were also sent a health and life experiences questionnaire (see the page on psychosocial measures in our collaborators' section).

Second health check (three years)
Three years after the first health check, all participants were invited back for a second health check in which most measurements performed at the baseline health check were repeated. Also, the participants completed a second follow-up health questionnaire, a twenty-four hour diet recall, a food frequency questionnaire and a seven-day food diary. Some measures obtained were not carried out at the baseline health check: heel ultrasound measurements of each foot were performed and percentage body fat was estimated. Participants also completed a questionnaire on their physical activity (a PDF version of this questionnaire is available here and associated data entry and processing program here).

Third health check (Thirteen years)
We are now embarking on the Third Health Check (3HC) of the EPIC-Norfolk study. The aim of the 3HC is to firstly resurvey participants in the cohort and obtain repeat measures to add to the information we have from the previous two health checks; and secondly, to expand the study further by including new measures. In this phase, we plan to investigate physical and cognitive function to see what happens to our minds and bodies as we age and things get more difficult both mentally and physically, and we find it harder to remember, or to do normal daily chores and look closely at the lifestyles of those people who seem to have better health and memory. We will also carry out a detailed eye assessment using some of the latest technology in optic nerve and retinal photography investigating the eyes and vision and how lifestyle and environmental factors influence a person's risk of developing eye disease, in particular, glaucoma and age macular degeneration which are two major causes of irreversible blindness in this country. Please visit the Third Health Check page for more information.

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