Common Lab Tests Explained: CBC, CMP, Lipids, A1C

This reference explains common lab tests you’re likely to encounter and what they typically mean. Use it to interpret results and prepare informed questions for your clinician.

Complete Blood Count (CBC)

The CBC measures components of blood: hemoglobin (oxygen-carrying protein), hematocrit (percentage of red cells), white blood cells (immunity), and platelets (clotting). Abnormalities suggest anemia, infection, or bleeding disorders and often require follow-up tests to determine cause.

Comprehensive Metabolic Panel (CMP)

The CMP includes glucose, electrolytes, and kidney and liver function tests. Changes can indicate metabolic problems, dehydration, kidney disease, or liver injury; repeat measurements and correlation with symptoms are commonly required.

Lipid Panel

Cholesterol and triglyceride levels are used to assess cardiovascular risk. Management often includes lifestyle changes and, when indicated, medications like statins.

Hemoglobin A1C

A1C reflects average blood glucose over several months; it’s used for diabetes screening and monitoring. Results are categorized into normal, prediabetes, and diabetes ranges.

When to talk to your doctor

If tests are out of range and persistent, ask your clinician whether additional testing, lifestyle changes, or treatment is needed.