By Tanya Noyes, Grace Cottage Lab Director

You’ve just finished a clinic visit with your primary care provider, and you’ve been sent to the lab for a blood test. What happens next?

Blood and other specimen tests are a vital part of your provider’s diagnosis, helping to determine what course of action is best for your medical care. But lab testing happens behind closed doors (for privacy and safety reasons). As a result, the role of clinical lab professionals is one of the least understood in health care, even though there are approximately 340,000 laboratory professionals in the United States.

Medical Laboratory Professionals Week, April 19-25, 2026, provides the perfect opportunity to learn more about this profession, and just as importantly, to learn what happens to your blood sample after it’s drawn.

According to the American Clinical Laboratory Association, more than 7 billion lab tests are performed in the U.S. each year, providing critical data about your health for a relatively small cost. “Clinical laboratory tests save time, costs, and lives by enabling early detection and prevention of disease,” the Association’s website explains.

Lab tests range from a heel stick of a newborn baby to tests for bilirubin, to highly complex tests requiring Medical Laboratory Professional expertise. Most tests are considered moderately complex. Regardless of complexity, test results provide helpful, sometimes critical, lifesaving information to healthcare providers and their patients.

Before a blood test, you stop at registration, where you will be asked your name and date of birth. You are asked for this information multiple times throughout your visit. No, we’re not forgetful! Proper identification is so important that double and triple checking this information helps to ensure that the blood samples get labeled correctly. What good are accurate lab results if they’re not your results?

Patient identification is critical and is fundamental to the entire lab process. At least two unique identifiers, such as name and birthdate, are required on all specimens prior to testing. These should be labeled in your presence, before you leave the lab. If you’re dropping specimens off, be certain to include your full name and date of birth on all specimen containers.

Once collected, blood specimens are routed to different areas within the lab. Specimens arriving from the emergency room are marked STAT and are given priority.

Many of the tests are performed using the highly automated analyzers that test chemistry, hematology, coagulation, and urinalysis. Chemistry and hematology analyzers are the “workhorses,” handling the largest number of tests.

Most chemistry blood specimens require centrifugation prior to testing. Tubes of blood are spun at high speed, forcing cells to the bottom, separating out the liquid required for many tests, including glucose, potassium, sodium, cholesterol, liver and kidney enzymes, vitamins, and the level of therapeutic drugs to see whether dosage needs to be adjusted.

While chemistry focuses on the liquid portion of blood, hematology uses whole blood to look at the cells within your blood. Basic hematology testing includes measuring the number of red and white blood cells and platelets.

Sometimes the results will lead a lab tech to make a smear of the blood so it can be examined with a microscope. The microscope allows the tech to look at individual cells, and as “detectives,” we scan your blood to look at immature cells or all the different shapes, inclusions, and possible microorganisms of the cells. This scan gives your provider valuable information for clinical decisions. A microorganism can be seen in your white blood cell, and having a low platelet count indicates that you may have gotten bitten by a tick and you may have anaplasmosis.

White cells are a vital part of our immune system and help to fight infections. An increase in the number of white cells may indicate infection, and higher percentages of certain types of white cells may be clues to the infection’s source, whether bacteria, virus, or parasites. When examined microscopically, white cells may also reveal the onset of various diseases.

While automation plays a vital role in the lab, that role should not be overestimated. Interpreting the results requires special knowledge. Clinical lab professionals are often the first to observe unusual results that trigger the need for further investigation. Less automated areas of the lab, like microbiology and the blood bank, still rely heavily on a lab tech’s experience.

All clinical labs in the U.S. are highly regulated by the federal government. They must hold a Clinical Lab Improvement Act (CLIA) license and undergo regular and rigorous inspections, insuring quality results and patient safety. Certified lab personnel must pass board exams. Like other medical professionals, they are required to maintain their certification with continuing education and are continually required to perform proficiency testing, with results compared nationally to their peers and reviewed by CMS. This level of scrutiny, along with mandatory quality control, should provide confidence in your test results.

Like all hospitals in our region, Grace Cottage cooperates with other labs. Not every lab can perform every possible blood test. Unusual tests are generally referred to large national and regional labs. Grace Cottage can collect any sample your doctor orders, even if the sample must be sent elsewhere for testing.

Hopefully this article has provided a glimpse into the role that clinical lab techs play in your healthcare. We’re kind of like detectives, working behind the scenes to uncover valuable clues to your health!