1. The Northern Sweden MONICA myocardial registry, Department of Research, Norrbotten County Council, 971 89 Luleå, Sweden
2. Department of Nursing, Umeå University, 901 87 Umeå, Sweden
3. Department of Medicine, Sunderby Hospital, 971 80 Luleå, Sweden
4. Department of Public Health and Clinical Medicine, Umeå University, 901 87 Umeå, Sweden