If you're storing labs, like blood counts or cholesterol levels, create a new entry and write down the name of the test. Then tap the "lab" button and select the body fluid.
For imaging like ultrasound, CT, X-ray, MRI, write down the name of the test. Then tap the # button and select #rad for radiology. Other tests can be categorized by specialty as well, like #cv for cardiology (stress test) or #gi for colonoscopy.
And that's it! It's really that easy to keep track of your labs, Xrays, MRIs, ultrasounds, and other clinical tests!