​​About Laboratory Medicine Professionals

Various health care professionals work in our laboratory at UHN, providing high-quality lab medicine and care for our patients. Our laboratory professionals often work behind the scenes to help physicians diagnose and treat patients, as well as monitor and prevent diseases through laboratory testing, diagnoses and analysis.

Medical Laboratory Technologists

Medical laboratory technologists (MLTs) are the fourth-largest group of health care professionals in Ontario. They work in all areas of our laboratory, including biochemistry, hematology, molecular genetics, pathology and microbiology, as well as in UHN's research labs. The role of an MLT is to perform complex procedures on tissue specimens, blood samples and other body fluids in order to provide vital information that allows physicians to diagnose, treat and monitor a patient's condition.

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Medical Laboratory Technicians

Medical laboratory technicians (also referred to as medical laboratory assistants) work alongside MLTs, but their day is focused on more of the prep work required for testing and diagnoses. Medical laboratory technicians are responsible for collecting and receiving blood, tissue and other samples from patients, logging samples and preparing them for testing, performing routine tests and sample analyses, and setting up, cleaning and maintaining laboratories and equipment.

Pathologists' Assistants

Pathologists' assistants (PAs) are highly trained laboratory professionals who work under the supervision of a pathologist, providing a broad range of services in anatomic pathology. Pathologists' assistants are primarily responsible for the initial examination and dissection of all surgically removed tissues and, in some cases, for the dissection of bodies during post-mortem examinations.

What is the difference between a medical laboratory technologist and a medical laboratory assistant/technician?

In the Laboratory and Specimen Collection Centre Licensing Act of 1990, the Ontario Ministry of Health and Long-Term Care defines a medical laboratory technologist and a medical laboratory assistant/technician as different roles in terms of education, experience and responsibilities.

Educational programs for both medical laboratory technologists and medical laboratory assistants/technicians are accredited by the Canadian Medical Association's Conjoint Committee on Accreditation, and graduates of accredited programs are eligible to write the national certification examinations, conducted by the Canadian Society for Medical Laboratory Science, or the provincial certification exams, conducted by the Ontario Society of Medical Technologists.

A medical laboratory technologist is a regulated health care professional in Ontario under the Regulated Health Professions Act, 1991 and the Medical Laboratory Technology Act, 1991. After obtaining certification, a medical laboratory technologist must register with the College of Medical Laboratory Technologists of Ontario to be able to practise in the province. At this time, medical laboratory assistants/technicians are not regulated professionals in Ontario, but the College of Medical Laboratory Technologists of Ontario is working toward regulating this important laboratory medicine role in the future.

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