Why is PhysioNet here?
You can’t learn everything there is to know about snow by studying a single snowflake, or even a few hundred of them. In much the same way (and for some of the same reasons), physiologic signals display astonishing diversity, between individuals and even within individual subjects over time. To study them seriously requires large amounts of data that are difficult and expensive to gather and to characterize, and software that can be flexibly and efficiently modified to meet the unique requirements of new research. PhysioNet is here first of all because we (see the previous question) needed to gather such data and to design such software for our own work. Having done so, we believe that other researchers should not be forced to do the same, and that by making our data and software available, others should be able to explore them, to develop, test, and refine hypotheses; in short, to do investigations that would not be possible otherwise.
