---
title: "Medical laboratory scientist"
chunk: 1/7
source: "https://en.wikipedia.org/wiki/Medical_laboratory_scientist"
category: "reference"
tags: "science, encyclopedia"
date_saved: "2026-05-05T03:47:55.874604+00:00"
instance: "kb-cron"
---

A medical laboratory scientist (MLS), clinical laboratory scientist (CLS), or medical technologist (MT) is a licensed healthcare professional who performs diagnostic testing of body fluids, examples: blood, urine, sputum and other body tissue. The medical technologist is tasked with releasing the patient's results to aid in further treatment. The scope of a medical laboratory scientist's work begins with the receipt of patient or client specimens, and finishes with the delivery of test results to physicians and other healthcare providers.
The utility of clinical diagnostic testing relies squarely on the validity of test methodology. To this end, much of the work done by medical laboratory scientists involves ensuring specimen quality, interpreting test results, data-logging, testing control products, performing calibration, maintenance, validation, and troubleshooting of instrumentation as well as performing statistical analyses to verify the accuracy and repeatability of testing. Medical laboratory scientists may also assist healthcare providers with test selection and specimen collection and are responsible for prompt verbal delivery of critical lab results. Medical laboratory scientists in healthcare settings also play an important role in clinical diagnosis; some estimates suggest that up to 70% of medical decisions are based on laboratory test results and MLS contributions affect 95% of a health system's costs.

The most common tests performed by medical laboratory scientists are complete blood count (CBC), comprehensive metabolic panel (CMP), electrolyte panel, liver function tests (LFT), renal function tests (RFT), thyroid function test (TFT), urinalysis, coagulation profile, lipid profile, blood type, genotype, pack cells volume (PCV), hepatitis (HbsAg and HCV), glucose test (fasting blood sugar {FBS} and random blood sugar {RBS}), Endo cervical swab (ECS), high vaginal swab (HVS), semen fluid analysis (for fertility and post-vasectomy studies), serological studies and routine cultures. In some facilities that have few phlebotomists, or none at all, (such as in rural areas) medical laboratory scientists may perform phlebotomy. Because medical laboratory scientists have many transferable technical skills, employment outside of the medical laboratory is common. Many medical laboratory scientists are employed in government positions such as the FDA, USDA, non-medical industrial laboratories, and manufacturing.
In the United Kingdom and the United States, senior laboratory scientists, who are typically post-doctoral scientists, take on significantly greater clinical responsibilities in the laboratory. In the United States these scientists may function in the role of clinical laboratory directors, while in the United Kingdom they are known as consultant clinical scientists.
Though clinical scientists have existed in the UK National Health Service for ≈60 years, the introduction of formally-trained and accredited consultant-level clinical scientists is relatively new, and was introduced as part of the new Modernizing Scientific Careers framework developed in 2008.
Consultant clinical scientists are expected to provide expert scientific and clinical leadership alongside and, at the same level as, medical consultant colleagues. While specialists in healthcare science will follow protocols, procedures and clinical guidelines, consultant clinical scientists will help shape future guidelines and the implementation of new and emerging technologies to help advance patient care.
In the United Kingdom, healthcare scientists including clinical scientists may intervene throughout entire care pathways from diagnostic tests to therapeutic treatments and rehabilitation. Although this workforce comprises approximately 5% of the healthcare workforce in the UK, their work underpins 80% of all diagnoses and clinical decisions.