Digital Health

We only have about a million physicians in the United States — but they’re about to get reinforcements.

If you think about the CAT scan that an MD is using, if you think about almost any modern device that a doctor is using — it’s useless without the code in it. That code was likely written by someone without an MD, someone who was evaluated as competent and hired by a commercial vendor of mission-critical medical instruments. The instruments that represent the foundation of modern medicine are thus today typically programmed by people who know how to code (but lack MDs) and used by people who have MDs (but usually do not know how to code).

So a large percentage of medicine is already being effectively practiced by non-MDs.

Moreover, the interior workings of the instruments are black boxes; MDs interface with them through vendor-provided UIs and interpret the readouts by looking up data stored in their head. As these UIs get better and smarter, less interpretive skill is required by the MD. The MD is happier — the instrument gets the right answer with less work. It’s used more frequently. Through successively more sophisticated engineering the instrument thus begins to move from the hands of the specialist to the generalist to the nurse practitioner to the nurse… and then, perhaps, to the general population in the form of a phone accessory or an app.

That last step is starting to happen as various personal genomic, quantified self, and mobile diagnostic technologies become more accessible. These technologies produce data from the body, and that data is going to be stored in our phones. The interpretation of that data is going to be performed by software.

And so that large percentage of medicine that is effectively being practiced by non-MDs is going to expand.

One center of action is likely going to be the mobile programmable medical record — the container for all diagnostics and test results — something like what Apple’s HealthKit may evolve into. Essentially just a bunch of data containers for your heart rate history, your blood pressure history, your exercise history, and the like.

All this diagnostic history isn’t necessarily “big data”; it’s just never been tracked and cross-correlated before in one place. Once technologies like HealthKit get a little more traction, millions of software engineers without MDs can build new applications on top of that data store (perhaps collected by other applications) without injuring the phone owner.

Today you’d accept without hesitation that the kid in the garage without a degree could write an email front-end that analyzed your email, told you the best time of day to reply, or did something else interesting, unexpected, and useful with your email data. Tomorrow? To understand your personal diagnostic data, you might soon depend more upon an iPhone app developed in a garage than on your local MD.

— Balaji S. Srinivasan




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