Between May 1991 and January 1994, a sample of 10 600 men aged 50-59 years was examined in one centre in Northern Ireland (Belfast; n=2745) and three centres in France—Lille in the north (n=2633), Strasbourg in the east (n=2612), and Toulouse in the south west (n=2610). Of these 10 600 participants, 842 (7.9%) were excluded because of a medically diagnosed history of angina pectoris or myocardial infarction, or because of chest pain at entry according to the Rose questionnaire. A total of 317 (3.0%) men were lost to follow-up after 10 years, 215 (2%) refused to continue participating in the study, and 653 (6.1%) died in the course of follow-up. The proportion of refusals and participants lost to follow-up was similar in Belfast and the French centres (150/2745 (5.5%) and 382/10 600 (3.6%), respectively). The number of men included was 9778 in total: 2405 and 7373 in Belfast and in the French centres, respectively.
