Cardiovascular registry research comes of age

> No matter how beautiful the strategy, you should occasionally look at the results. Winston Churchill Registry research is gaining increasing visibility within cardiovascular medicine. Randomised controlled trials (RCTs) are rightly at the top of the hierarchy of evidence for determining clinical efficacy. However, the characteristic that makes the RCT so powerful in establishing internal validity—control—limits the ability to provide a comprehensive picture of clinical medicine as it is practised. As in the Churchill quote above, RCTs may be able to provide the basis for the most ‘beautiful’ management strategies, but determining how these strategies work in the ‘real world’ is critical. In addition to these limitations in external validity, practical problems such as cost, time horizon and breadth of questions leave a clear need for many types of observational research. Registries across the globe are actively examining many aspects of this need. As with all study types, critical assessment of the structure, strengths and weaknesses of registries is necessary in order to gain an appropriate perspective of where this research fits into the broad picture of cardiovascular medicine. To this end, Heart will publish a new series of articles describing some of the most important registries of patients with acute coronary syndrome and other cardiovascular disorders. How can registry research contribute to filling the knowledge gap? In his 2000 editorial entitled ‘Are data from clinical registries of any value’, Alpert articulated a well-reasoned affirmative answer to this question.1 Gitt and colleagues recently published an updated defence of cardiac registries in evidence-based medicine.2 Briefly, registries …