In modern health care, medical datasets are increasingly being used to improve patient care, including through population health analysis and the development of diagnostic machine learning algorithms. This trend has been a key driver for the development of open-access datasets, giving researchers access to local or national data shared by different institutions. Open-access data can be used to train machine learning algorithms on diverse datasets that have been carefully curated, or to test algorithms that have already been trained by researchers elsewhere to assess their performance when applied to new data.