Evidence-Based Health Guides

REXQU Health Guides

Plain-English health guides where every figure is sourced to a named authority — WHO, the CDC, the American Heart Association or peer-reviewed research — and every guide states clearly what a wearable device cannot do. Free to share and republish with attribution.

Guides

More are added regularly. If you are a writer or clinician and spot an error, we want to know — email support@rexqu.com.

Understanding Your Blood Pressure Numbers

What the two numbers mean, the and/or trap most people miss, why the AHA and WHO disagree on where “high” starts, and the measurement mistakes that skew readings.

Sources: WHO · AHA · ESC

Can a Smartwatch Detect AFib?

Atrial fibrillation causes one in seven strokes and often has no symptoms. What a single-lead wrist ECG can flag, and what it cannot diagnose.

Sources: CDC · AHA

Falls in Older Adults: What the Data Says

More than one in four over-65s falls each year and fewer than half tell a doctor. The numbers, the fixable causes, and what fall detection really does.

Sources: CDC

Blood Oxygen (SpO2): What the Number Means and Where It Fails

A pulse oximeter reading is an estimate with a margin wider than the thresholds it is judged against — and the error is documented to be larger for people with darker skin.

Sources: FDA · NEJM · AHRQ · NHS

Why these exist

Most wearable health content is written to sell something. These are written to be accurate, including where the evidence is inconvenient — for example, that cuffless blood pressure devices are not validated for clinical decisions, and that fall detection does not prevent falls. If that costs us a sale but saves someone from trusting the wrong number, that is the right trade.