Mayo Clinic medical laboratory scientist working in a lab

What does a medical laboratory scientist do?

A medical laboratory scientist (MLS), also known as a medical technologist or clinical laboratory scientist, works to analyze a variety of biological specimens. They are responsible for performing scientific testing on samples and reporting results to physicians.  

Medical laboratory scientists perform complex tests on patient samples using sophisticated equipment like microscopes. The data they find plays an important role in identifying and treating cancer, heart disease, diabetes, and other medical conditions. It is estimated 60 to 70 percent of all decisions regarding a patient's diagnosis, treatment, hospital admission, and discharge are based on the results of the tests medical laboratory scientists perform.

Scope of practice

Medical laboratory scientists collaborate very closely with physicians and medical laboratory technicians in diagnosing and monitoring disease processes, as well as monitoring the effectiveness of therapy. Areas of medical laboratory training include microbiology, chemistry, hematology, immunology, transfusion medicine, toxicology, and molecular diagnostics. 

Medical laboratory scientists have a wide variety of responsibilities and duties, including:

  • Examining and analyzing blood, body fluids, tissues, and cells
  • Relaying test results to physicians
  • Utilizing microscopes, cell counters, and other high-precision lab equipment
  • Cross matching blood for transfusion
  • Monitoring patient outcomes
  • Performing differential cell counts looking for abnormal cells to aid in the diagnosis of anemia and leukemia
  • Establishing quality assurance programs to monitor and ensure the accuracy of test results
  • Overseeing the work of a medical laboratory technician

Medical laboratory scientist vs. medical laboratory technician

While similar, there are a few key differences between a medical lab scientist and a medical lab technician. They both work in the lab and perform tests on biological samples, however, a medical lab scientist typically has more education and is able to perform more involved lab work. A medical lab technician performs more of the routine lab work and is often supervised by a medical lab scientist.

Medical laboratory scientist vs. medical laboratory assistant

A medical laboratory assistant is a subgroup of medical laboratory technician. They are responsible for preparing biological specimens, recording information, and perform more of the lab maintenance tasks such as cleaning equipment and stocking supplies. A medical laboratory scientist will work with a medical laboratory assistant by analyzing their prepared specimens and relaying information for them to record.

Work environment

Medical lab scientists work in hospitals, clinics, forensic or public health laboratories, as well as pharmaceutical industries, biotechnology companies, veterinary clinics, or research institutions. Depending on the setting, their work hours may vary; but typically labs are run 24 hours a day, seven days a week. This allows for flexibility in scheduling.

Medical laboratory scientists spend the majority of their time on their feet, analyzing test results in the lab.   

Becoming a medical laboratory scientist

Successful medical lab scientists are effective communicators with a sound intellect and interest in science and technology. Excellent eye-hand coordination, dexterity, and visual acuity are important to skillfully perform and analyze tests. 

Individuals that love science and research, but prefer to have little-to-no interaction with patients, would be a good fit for the medical laboratory scientist career.

Higher education requirements

After obtaining a high school diploma (or the equivalent), most will go on to obtain some level of higher education and training in order to become a medical laboratory scientist.

Common higher education requirements for medical laboratory scientist jobs include:

  • Completing a bachelor’s degree in medical technology or clinical laboratory science. A bachelor’s degree in a science or health related field (e.g. chemistry or microbiology) may also be considered.
  • Completing a clinical laboratory program or internship through a hospital-based program or as part of their education
  • National certification as a medical technologist (MT), clinical laboratory scientist (CLS), or medical laboratory scientist (MLS)
  • Previous experience in a health care setting

Certification and licensing

Most employers require medical laboratory scientists to obtain certification through an accrediting body, such as the American Society for Clinical Pathology (ASCP) Board of Certification (BOC). After passing the credentialing exam, medical laboratory scientists (MLS) can practice under the credentials of MLS(ASCP)CM.

Licensure by state may also be required.

Career opportunities and outlook

The median salary for a medical lab scientist ranges between $52,000-$71,000 depending on education and previous experience.

Job growth and security is high for medical laboratory technicians and scientists. According to the Bureau of Labor Statistics, there is currently a shortage of medical lab technicians and scientists in many parts of the country which guarantees ample employment opportunities and sometimes higher salaries for graduates. With the volume of laboratory tests continuing to increase due to both population growth and the development of new types of tests, job opportunities are expected to continue to increase faster than average with over 22,000 new positions expected to be available by 2022.

With additional training and experience, a medical lab scientist can become a department lead or lab manager. Others may seek specializations to advance their careers. Typically, a medical lab technician will progress to a medical lab scientist with more training.

By the numbers

Medical laboratory scientist programs at Mayo Clinic

Mayo Clinic offers several programs and rotations to further your education and prepare you for a career as a medical laboratory scientist, medical laboratory assistant, or medical laboratory technician.

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