You can't exchange data without thoroughly understanding the clinic workflows that generated it or will be using it. It's all time-consuming and hard.
I work on a patient portal consuming data from the EMR, and even that is tremendously complicated to present medical data safely and correctly to a person.
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Sibling comment mentioned wanting to work in Health IT. The big market problem in healthcare is small companies doing good innovation (usable patient-side workflows, modern clinical tools, shiny things) running into the consolidated, massive EMR systems. The first question when they approach a healthcare system will be "Are you integrated with Epic/Cerner/whatever?" and if not, they will be sent away. Or be ready to embark on a very long, slow process and integrate deeply into workflows, data APIs, etc.
When a system consolidates their EMR (driven by real needs but also Meaningful Use incentives), it forces standardization and special one-offs become much harder. Getting a doctor interested in using a new device or software means working within the whole EMR - the staff doesn't have the time or leeway to go use tools that don't integrate, just because a doctor really wants it. That doctor needs to align large groups, get agreement, and it's going to take a lot of time and money.
It all comes down to interoperability/integration. Building cool stuff in healthcare is really easy since most of the tech in use is outdated and slow moving. But interoperability - required to sell into healthcare systems - is really, really tough.