Your doctor says everything looks fine, but you still feel terrible. The problem might not be your health but how labs define “normal.” Understanding the difference between normal and optimal could ...

Lab tests are interpreted based on reference intervals. Normal ranges and reference intervals But this all raises the question: What actually counts as too high or too low on a blood test?

A red blood cell (RBC) count measures the number of red blood cells in a sample of blood. It is part of a battery of tests called a complete blood count (CBC) that measures the different types and ...

In medicine, a person’s blood-test results are compared with the average range in a population. But results are highly individual and tightly regulated around a person’s own stable values. Changes to ...

This article was reviewed by Darragh O’Carroll, MD. Blood tests are one of the most widely used and helpful tools in modern medicine. Whether ordered in a clinic or done through an at-home kit, they ...

Biomarker lab tests typically take a biological sample, like blood, to evaluate certain biomarkers, which are measurable indicators of your health. Whether you're checking your hormones, thyroid, or ...

This is read by an automated voice. Please report any issues or inconsistencies here. You don’t feel like yourself. Maybe you’re low on energy, you’re not sleeping well, or your mood feels harder to ...

You receive a phone call: the results from routine blood tests show a “low white cell count”. Your doctor explains that more investigations are necessary, perhaps a referral to the haematologists.

DEAR DR. ROACH: I am a 73-year-old female. A recent blood test returned an eGFR (estimated glomerular filtration rate) of 59. My physician’s nurse told me that the test was normal. When I asked her ...

If you’ve ever had a doctor order a blood test for you, chances are that they ran a complete blood count, or CBC. One of the most common blood tests in the world, CBC tests are run billions of times ...