There's a number that predicts whether you'll be alive in ten years better than your blood pressure, your cholesterol, your BMI, or whether you smoke. The American Heart Association has been recommending it as a vital sign since 2016. Your doctor has almost certainly never measured it. Apple Watch measures it every time you take a brisk walk.

As AI and smartphones put more diagnostic power into consumers’ hands, healthcare faces disruption not just within the clinic—but beyond it. From OTC drugs to pneumonia-detecting apps, selfcare is rising fast. This isn’t the future. It’s already here—and it’s shrinking the doctor’s role.

Smartphone apps that can diagnose pneumonia? FDA-approved machines that can diagnose conditions without a doctor? Robot psychotherapy? It’s not coming, it’s here now.

Most doctors, nurses, PAs, techs, and others in healthcare aren’t familiar with the term “disruption” and are unaware of how technological trends have already begun disrupting their current business models. This post is the first of three that will provide a basic understanding of the term, and the phenomenon.