The world’s largest randomised trial to date of a medical device in myocardial infarction patients was performed by applying the Swedish patient registry SWEDEHEART. No less than 7,244 patients were included in the study with minimal extra work since patient data was easily accessible. Additionally, because clinical endpoint parameters were obtained from health national registries, no study-specific clinical follow-up was needed.
The study received widespread international attention. Many observers were astonished that such a large study could be conducted and published in just a few years as a randomised study including nearly all current patients in Sweden. Furthermore, at a fraction of the normal cost for a study of that size.