Lab Testing Guides
Practical, source-cited guides to help you understand and order lab testing. Browse by topic below.
These guides explain what common lab tests measure, why they are ordered, how to prepare for collection, and how to read results in plain language. Each guide is researched against public health and clinical sources and lists the references it uses.
If you are not sure where to start, browse by topic below, or use the search box to find a specific test such as cholesterol, cortisol, or thyroid. Each guide also links to related tests that are often ordered together.
How to use this directory
Browse by topic or cluster to see every guide in a broad area such as thyroid, cardiac, or metabolic testing. If you already have a test in mind, search by name, for example cholesterol, cortisol, or thyroid. Each guide covers preparation, timing, related tests, and where testing is available, and is educational rather than a substitute for advice from a healthcare provider.
Guide Library FAQ
What do these guides cover?
They explain what common lab tests measure, why they are ordered, how to prepare, and how results are reported. Each guide focuses on one test or a group of related markers.
How do I find the right test?
Start with the topic that matches your concern, or search by test name such as cholesterol, cortisol, or thyroid. Each guide links to related tests often ordered together.
Are these guides medical advice?
No. They are educational and explain how tests work and what they measure. Discuss results and testing decisions with a healthcare provider.
Browse by Topic
General Lab Testing
Everyday lab testing topics: how tests work, how to read results, and what to order.
Metabolic, Vitamins & Minerals
Blood sugar, cholesterol, vitamins, minerals, and metabolic markers.
Hormones & Fertility
Testosterone, estrogen, cortisol, fertility, and related hormone tests.
Thyroid
TSH, T4, T3, thyroid antibodies, and thyroid conditions.
Heart & Cardiac
Heart markers, lipids, inflammation, and cardiac risk testing.
Allergies
Food, pollen, pet, mold, and other allergy blood testing.
STD Testing
STD and STI testing: panels, window periods, and what each test detects.
Hepatitis
Hepatitis A, B, and C testing and immunity.
Tuberculosis
Tuberculosis (TB) testing.
Kidney
Creatinine, BUN, urine protein, and kidney function testing.
Autoimmune
Autoimmune markers such as ANA, rheumatoid factor, and related tests.