VistA, the EHR of the Veteran’s Administration (VA), is available to all-and-sundry, thanks to the freedom of information act (FOIA). Anyone can download, what is arguably, the most widely used, enterprise-grade, EHR in America, and use it for free. Obviously any hospital considering a new EHR should give it a once-over.

The VA presents VistA as a set of packages – a pharmacy package, a lab package, a vital’s package, on and on – but we don’t care about these apps (let’s use today’s term for package): our interest is in the patient care data they produce. For us, VistA – or any EHR – is a patient data repository and doctors, nurses are all data-entry people. From this perspective, VistA can be cut into four neat slices, all wrapped in a crust …

Let’s start on the outside and work our way in: any information queried from VistA will follow its schema. There’s schema for a patient, a hospital and its personel, for describing drugs – nearly 2500 buckets into which VistA pours its data.

Next up – VistA’s concepts. You can judge an EHR’s expressiveness by the breath of its concept support and by this reckoning, VistA is very articulate. It has the usual standard suspects – ICD9, CPT, NDC , even Drug Manufacturers – as well as national VA definitions for Drugs, Lab tests … and then there are locally-defined concepts, notions particular to each VistA installation, many with no standard equivalents.

Here’s VistA Goodness: a comprehensive model for patient data that leverages an extensive set of concepts. For someone greedy for real-world health-data, VistA’s the mother-lode – and it’s free!

Hold on, you’ll cry – if you’re into health-data standards. What we have here is a proprietary schema for patient data which will use non-standard concepts and not just those from the VA but even locally-defined notions! What kind of patient-data exchange is this good for? Such data can’t be used beyond the world of VistA!

But that’s the beauty of VistA for us. When we show how easy it is to make Caregrafs from VistA data, despite all of its quirks and vista-ese then a good idea will no longer be academic. We’ll have proven that real-world, enterprise-scale EHR information is at home in the web-of-data, that’s there’s no gulf between the technology deployed today and where most believe data is best handled. In a nutshell, VistA’s our New York – you know the ditty, if I can make it there ….