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Clinical Laboratory Scientist Training Program

The Clinical Laboratory Scientist (CLS) Training Program was established in 1958 by the Department of Pathology & Laboratory Medicine at UC Irvine Medical Center in Orange, California. This program was previously referred to as the Medical Technology Training Program (i.e., CLS, Medical Technologist {MT}, and Medical Laboratory Scientist {MLS} are often used interchangeably). The program is approved by the California Department of Public Health, the National Accrediting Agency for Clinical Laboratory Sciences (NAACLS) and the UC Irvine Allied Health Committee.  

The CLS Training Program provides a full year of didactic and clinical instruction. The curriculum includes intensive bench training, formal and informal lectures, and case studies. Students receive more than 200 hours of formal lectures covering the various disciplines of clinical laboratory science. The instructor-student ratio for lecture sessions is 1:6. Training in the clinical laboratories takes place with an instructor-student ratio of 1:2 to 1:6.

After fulfilling all program requirements, students receive a certificate of completion and are eligible to take the external exam leading to licensure as a California CLS and certification as a Medical Laboratory Scientist MLS by the American Society for Clinical Pathology (ASCP).

Program Director Ellena Peterson, PhD, F(AAM), CLS, MT(ASCP)
Program Medical Director Luis M. de la Maza, MD, PhD

National Accrediting Agency for Clinical Laboratory Sciences (NAACLS)
5600 N. River Road, Suite 720
Rosemont, IL 60018-5199
(773) 714-8860

California Department of Public Health
Laboratory Field Services (LFS)


LFS Northern California Office
850 Marina Bay Parkway
Building P, 1st floor
Richmond, CA  94804
(510) 620-3800

LFS Southern California Office
320 West 4th Street, Suite 890
Los Angeles, CA  90013
(213) 620-6160

Application Period September 1 - November 1
Training Positions/Class Up to 6
Program Start Date First week in July; one class per year
Program Duration

One year of full-time training

Monday to Friday, 40 hours/week

Fees/Cost No tuition; student is responsible for costs associated with health insurance, parking, transportation, textbooks, licensing and certification exam fees, and immunizations as required for health clearance
Stipend/Scholarship A scholarship is provided to admitted students, paid on a monthly basis; amount is dependent on annual budget


The mission of the CLS Training Program is to provide a learning environment in which students acquire the academic knowledge, technical skills, professional behaviors, critical thinking, and problem-solving ability necessary to become a proficient CLS.  

Program Goals

To provide a learning experience that will:

  • Stimulate and challenge the student to become educated in the principles of laboratory medicine
  • Teach the clinical significance of laboratory procedures in the diagnosis and treatment of patients
  • Provide an in-depth curriculum and clinical experience in an environment in which the problem solving and judgmental abilities of the student can develop and mature
  • Help develop an understanding of the principles, necessity and practices of quality assurance
  • Allow acquisition of the technical skills necessary to perform manual tests and operate complicated, state-of-the-art instrumentation 
  • Build problem-solving skills, become familiar with principles of research/evaluation methods and personnel/business management in a clinical laboratory 
  • Instruction in issues regarding patient rights, patient safety, patient privacy, and compliance with regulatory agencies
  • Instruction in environmental, health and safety practices necessary in a clinical laboratory
  • Assistance in the development of communication skills that will enable effective listening, reading, speaking, writing, and presentation of conecpts, ideas and information
  • Provide examples of professionalism, leadership, integrity, and compassion that can be observed and practiced
  • Demonstrate dedication to and the need for the continued acquisition of knowledge required for continuing professional development

Entry Level Competencies 

Upon completion of the CLS training program, at entry level as a CLS, individuals will possess the competencies necessary to perform the full range of clinical laboratory tests in areas of clinical chemistry, hematology/hemostasis, immunology, immunohematology, transfusion medicine, microbiology, urine and body fluid analysis, molecular diagnostics, laboratory operations, and other emerging diagnostics, and will play a role in the development and evaluation of test systems and interpretive algorithms. 

The CLS will have diverse responsibilities in areas of analysis and clinical decision-making, regulatory compliance with applicable regulations, education, and quality assurance/performance improvement wherever laboratory testing is researched, developed or performed. 

At entry level, the CLS will have the following basic knowledge and skills in:

  • Principles and practices of clinical study design, data analysis, implementation, and dissemination of results
  • Principles and practices of administration and supervision as applied to clinical laboratory science
  • Communications skills sufficient to serve the needs of patients, the public and members of the healthcare team
  • Principles and practices of professional conduct and the significance of continuing professional development
  • Educational methodologies and terminology sufficient to train and educate users and providers of laboratory service
  • Application of safety and governmental regulations and standards as applied to clinical laboratory science

Adapted from "Unique Standards for the Medical Laboratory Scientist, Core Standards for Accredited and Approved Programs". National Accrediting Agency for Clinical Laboratory Sciences (NAACLS), adopted 2012 (revised 2019).

Curriculum »

Throughout the training year, students participate, on average, in four hours of formal lectures per week. Lecture topics cover all laboratory disciplines and provide essential information for understanding the etiology and pathophysiology of disease, the principles of laboratory tests, and the clinical significance of laboratory test results. Presenters include pathology and laboratory medicine faculty, residents, and CLS.  

The majority of training time is spent in the working clinical laboratory where students observe, practice and perform clinical diagnostic testing under the direct supervision of their instructors. Students learn to perform manual procedures, operate highly sophisticated automated instruments, utilize laboratory computer systems, monitor quality control and review laboratory results for their validity. The program provides students the opportunity to greatly expand their scientific knowledge, develop proficiency in an array of technical skills, demonstrate the highest regard for patient care, and consistently display professional behavior.  

Blood Bank/Donor Center    

Students in the blood bank study transfusion medicine and immunohematology concepts. During the rotation, students practice blood banking tests, work with blood donors and process blood components. Problem-solving skills are assessed by practical exams. Time is also spent in apheresis observing plasma exchanges and cytapheresis as well as with hemotherapy services observing therapeutic phlebotomy and directed donations. 


The chemistry section includes rotations through automated and special chemistry, immunochemistry, toxicology, therapeutic drug monitoring, and urinalysis. Students perform a wide range of analytical procedures and learn to correlate laboratory data with clinical findings. They have the opportunity to work with a multitude of highly sophisticated automated technologies.  


During the rotation, students learn to identify normal and abnormal cells of blood, bone marrow and body fluids and learn manual/automated cell counting methods. Students are also introduced to flow cytometry and hemoglobin electrophoresis. Problem-solving skills are further developed in the coagulation lab while investigating disorders of hemostasis.


Students rotate through bacteriology, antimicrobic susceptibility testing, mycology, parasitology, serology, mycobacteriology, virology and molecular microbiology. They learn to evaluate cultures from a variety of body sites, identify a wide variety of human pathogens using identification techniques such as culture, direct microscopic exam, proteomics, nucleic acid assays, and immunoassays. Automated methods are also integrated where appropriate.   

Molecular Diagnostics 

Students are introduced to the use of molecular diagnostic techniques for patient diagnosis, treatment, and monitoring. They utilize these techniques in a number of applications including molecular microbiology, molecular pathology, and human leukocyte antigen (HLA) testing. 

Professional Practice

Students are exposed to various aspects central to the administration and maintenance of a clinical laboratory to include:

Laboratory information systems (LIS): Computer applications, interfaces with instrumentation and other information systems

Compliance and regulatory agencies: Healthcare regulatory agencies and compliance with required standards of operation

Laboratory management: Introduction to areas such as human resource management, laboratory operations, communications and quality assurance

Phlebotomy: Techniques of blood specimen collection and other processes in the pre-analytical phase of specimen testing

Education: Use of strategic methodologies to effectively teach and evaluate student learning outcomes

Research: Develop skills needed to prepare, analyze and present scientific data for application in the clinical laboratory


Students must successfully fulfill the minimum requirements in each section of the lecture and laboratory training areas. Performance will be evaluated throughout the training year based on didactic lecture exams, lab exams, practical exams, lab skills, work habits, and professional behavior.

Students will also have multiple opportunities to evaluate the overall program, lecture presentations, bench instructors and clinical rotations.

Admission Requirements »

Admission requirements are based on standards set by the California Department of Public Health.  

U.S. citizenship, permanent residency in the U.S., or DACA recipients

Academic Requirements 

Baccalaureate degree (biological sciences, biochemistry or microbiology recommended). 

To include:

18 semester units (27 quarter units) in biological sciences; must include separate courses in immunology, hematology and medical microbiology (other recommended courses include mycology, virology and parasitology)

16 semester units (24 quarter units) in chemistry; must include biochemistry and analytical or clinical chemistry

Three semester units (4.5 quarter units) in physics; must include principles of light and electricity

One college mathematics course, preferably calculus

Courses in anatomy, physiology, genetics, molecular biology and statistics are also highly recommended

All required courses must have been taken for a letter grade and a minimum grade of "C" achieved

All required courses must be completed by the end of May, prior to the start of training

If advanced beyond the primary application, proof of enrollment in or completion of medical microbiology, hematology, immunology, biochemistry, and analytical chemistry must be received no later than Feb. 15 of the application cycle

Minimum cum GPA in sciences of 2.7

No record of academic probation within the last three years of schooling

Candidates with foreign degrees must have a course-by-course credential evaluation from an acceptable agency and have 30 semester units (45 quarter units) in upper division science courses from an United States college/university. For more information concerning coursework evaluation from foreign institutions, please refer to information published by Laboratory Field Services.

Application and Selection Procedure »

Summary: Application Process

Primary Application:

Submit September 1-November 1
Must be filled out electronically
Email application to

Advanced to Secondary Stage

Notified by December 1 if advanced in the application process
Transcripts to be provided only if advanced
Three letters of recommendation to be provided only if advanced

Invited to Interview:

Notified by February 15 if invited to interview
Interviews take place in March
Accepted applicants notified by the end of March

1. Primary Application:

The due date for the initial application is November 1st. Applications will only be accepted between September 1-November 1.

A completed application form should be sent by email to The application is a fillable pdf form. Only this format filled and submitted electronically will be accepted. (Download form to local hard drive and use latest version of Adobe Acrobat or Adobe Reader for best results.)

At this stage of the application process, applicants should only submit the primary application. Transcript, letters of recommendation, and other documentation should not be submitted unless requested.

Reapplicants need to submit a new application form.

2. Advancement to the second stage of the application process:

By December 1 all applicants will be notified as to whether they are being advanced to the second stage of the application process.

Applicants advanced in the process will be asked to provide the following:

Official University Transcript(s)

Applicants selected from their primary application will be asked to submit transcripts from the institution(s) where they obtained their bachelor's degree and attended to fulfill any prerequisites.
NOTE: Applicants should only request transcripts be sent on their behalf if notified they are being advanced to the next stage of the application process.

Transcripts must be sent directly from the school registrar on behalf of the applicant.

If the college/university offers an electronic transcript option, this is the preferred transmission method rather than having transcripts sent by postal mail. Have transcripts sent to If electronic transmission is not offered by a registrar, then transcripts should be mailed to:

CLS Training Program
UC Irvine Medical Center
101 The City Drive South
Bldg. 54, Room 4700
Orange, CA  92868

NOTE: An official transcript is one that is signed by the registrar of the college/university attended, imprinted with the institutional seal, and emailed (preferred) or mailed directly from the registrar to the CLS program, without being accessible to the trainee.

Foreign degree transcript evaluations:
Please refer to the information published by Laboratory Field Services as to approved transcript evaluation services.

Letters of Recommendation

Three letters of recommendation are required.

NOTE: Applicants should only request letters of recommendation be sent on their behalf if notified they are being advanced to the next stage of the application process.

Only the UCI-CLS Program Recommendation Form will be accepted which is a fillable pdf. (Download form to local hard drive and use latest version of Adobe Acrobat or Adobe Reader for best results.) Applicants should electronically fill out the top of the form and indicate that they waive all rights to read the letter of recommendation. Subsequently, this form should be emailed to their recommenders to complete. Recommenders should be instructed to email this form to Should a recommender also want to send a letter on letterhead that is acceptable, but the recommendation form, where the applicant has waived their right to review the recommendation, needs to accompany the letter.

Trainee License

All candidates ultimately accepted into the CLS training program are required to have a clinical laboratory scientist trainee license from the California Department of Public Health (LFS). The trainee license will not be issued until after the bachelor's degree has been awarded (or prerequisite requirements have been met), but the application process should start well in advance of the program start date. Applicants advanced in the application process should initiate their trainee license application or be in a position to do so should they be accepted.

For additional information, contact:

Laboratory Field Services
850 Marina Bay Parkway
Richmond, CA 94804-6403

3. Interview/Acceptance Notification

Applicants selected to be interviewed will be contacted by February 15th.

Interviews will be scheduled in March.

Applicants will be interviewed by members of the CLS program admissions committee.

On the day of the interview, applicants will receive a tour of the laboratories and meet the CLS trainees.

The following are taken into consideration when selecting candidates to be admitted to the program:

  • academics
  • interview performance
  • letters of recommendation
  • motivation
  • professionalism
  • communication skills
  • clinical laboratory work experience
  • extracurricular activities


Individuals selected for the training program will be notified in writing with a written response of acceptance requested.

Individuals not advanced through the application process will be notified.

The University of California Non-Discrimination Statement:

The University of California, in accordance with applicable Federal and State law and University policy, does not discriminate on the basis of race, color, national origin, religion, sex, gender identity, pregnancy1, physical or mental disability, medical condition (cancer-related or genetic characteristics), ancestry, marital status, age, sexual orientation, citizenship, or service in the uniformed services2. The University also prohibits sexual harassment. This nondiscrimination policy covers admission, access and treatment in University programs and activities.

1. Pregnancy includes pregnancy, childbirth, and medical conditions related to pregnancy or childbirth

2. Service in the uniformed services includes membership, application for membership, performance of service, application for service, or obligation for service in the uniformed services.

Financial Information »


No tuition is charged for the training program

Scholarships will be offered to admitted students, paid on a monthly basis and dependent on annual budget

Access to the UC Library Network

Lab coats and personal protective equipment provided



Licensing/certification exam fees (approximately $500)

Parking at UCI Medical Center

Immunizations as required for health clearance

Proof of major medical insurance

Student Policies »

Student Advisement

From the time of admission, incoming students receive regular communication from the program director advising them of policies, requirements and other training issues. Students are provided with training guides which are reviewed during orientation and contain all policies and procedures related to the program. As students progress through the year, guidance is provided on professional and career-related topics.

In addition to the program director, each laboratory division has at least one education coordinator, usually a senior CLS, specialist or supervisor, who is available for assistance and guidance. Students can also seek counsel from the laboratory administrative director and program medical director.

All meetings and discussions of student concerns are held in confidence and take place in an office or other private area that can be closed off from public access. Whether a student is having personal or academic problems, or issues related to peers or laboratory staff, program officials strive to maintain sensitivity and impartiality in all situations.  

Service Work

Students will not be substituted for service work in place of regular, paid laboratory staff. Any service work performed by students outside of regular academic hours is noncompulsory.  

Withdrawal from the Program

A student desiring to withdraw from the program must present his/her intention and reason for withdrawal in writing to the program director. Upon review of the request, an exit interview will be scheduled. Documentation of the interview and written request will remain in the trainee’s file. Laboratory Field Services and all relevant UCI divisions/departments will be notified of the student’s withdrawal. Issuance of scholarship checks shall terminate upon withdrawal from the program. The student will return all medical center property upon termination.

Academic Progression

In order to progress in the CLS Training Program, students must successfully fulfill the minimum requirements of academic achievement. 

Training objectives and student competencies are well defined for each unit of instruction. Achievement of objectives and competencies may be documented through competency checklists, by achieving passing scores (70 percent or better) on lecture/laboratory exams and quizzes, and maintaining an overall “B” average in each rotation. Students must also achieve at least satisfactory ratings on each clinical rotation evaluation.  

Students are expected to develop a sense of professionalism, responsibility, and ethics related to patient care and learning. If a student is unable to achieve and maintain the level of performance required, the program is obliged to take steps toward probation and/or release from the program.  

Any combination of deficiencies in academic/laboratory/professional performance can result in probation, final probation or release from the program. Verbal and written warnings are issued to the student during the period when he/she is not meeting minimum standards of the program.  

Student Conduct  

Academic integrity: Students are expected to refrain from cheating and plagiarism, to refuse to aid or abet any form of academic dishonesty and to notify faculty or program officials about observed incidents of academic dishonesty. Any student caught cheating or performing other serious acts of intentional academic dishonesty will be dismissed from the program.
Unacceptable behaviors: Examples of behaviors that are unacceptable at any time during the training program include: excessive, unexcused absences; involvement in non-professional behavior involving patients, students, staff or instructors; failure to follow hospital and laboratory policies, unauthorized possession/use of a controlled substance during work periods; violence or threats of violence; and dishonesty, theft or misappropriation of university property. Such behaviors will not be tolerated and will be cause for dismissal from the program.

Corrective Action: Corrective action may be required for minor offenses or deficiencies or those situations in which the student knows or reasonably should have known that the performance or conduct was unsatisfactory. Initial corrective action will begin with oral counseling. A reasonable time period shall be allowed for the student to improve after the oral counseling. When the student's performance has not improved with oral counseling, written counseling shall be initiated. The written warning shall describe the nature of the offense, the method(s) of correction, and the action to be taken if the offense is repeated or the deficiency persists. The student has a right to request reviews of the action by using the Student Appeals Procedure.  

Release from the Program (Dismissal): If, after probationary and/or corrective action processes, the deficient performance is not resolved, the student shall be informed in writing of dismissal from the program. The notice shall specify the effective date of release, state the reason(s) for dismissal and state the student's right to request review of the action by the student appeals procedure. Issuance of scholarship checks shall terminate upon release from the program. Laboratory Field Services and all relevant UCI Pathology & Laboratory Medicine divisions/departments will be notified of the student’s release. The student will return all medical center property upon termination.  

Student Appeals Procedure: It is the policy of the university to encourage and facilitate the resolution of complaints in a prompt and equitable manner. The student appeals procedure is established for implementation when a student believes that he/she has received an unfair or inequitable evaluation. If the situation cannot be resolved by initial discussions with the immediate parties, an impartial grievance committee will be convened to review and determine the course of action.

Frequently Asked Questions »

QUESTION: I have a question whether specific courses will meet the UCI-CLS program prerequisite requirements. Who should I direct these questions to?

ANSWER: The prerequisites for the UCI-CLS program are the same as that used by Laboratory Field Services (LFS) which are set by the State of California. Our program will defer to LFS as to whether a specific course meets the prerequisite requirements. Therefore, questions as to specific prerequisites should be directed to LFS ( since they ultimately need to approve your courses to issue you a CLS trainee license.

QUESTION: What is the difference between a clinical laboratory scientist (CLS), medical laboratory scientist (MLS) and a medical technologist (MT)

ANSWER: All three describe the same profession. MLS is used by some states and the National Accrediting Agency for Clinical Laboratory Personnel (NAACLS), CLS is the term used by the California Department of Public Health. CLS replaced the older designation, MT.

QUESTION: Can I apply for the program while still taking courses?

ANSWER: Yes. You can submit your application as long as you complete all required courses in time to obtain a CLS training license from LFS in the year in which you intend to begin training.

QUESTION: Can I be taking courses while attending the program? 

ANSWER: No. All courses must be completed prior to the start of training so that you will be eligible for issuance of the CLS trainee license. The license must be in possession and current when training begins.

QUESTION: I have a bachelor’s degree, but not in biology, biochemistry or microbiology. Am I still eligible to apply? 

ANSWER: Yes. We recommend a degree in those sciences because many of their academic requirements overlap with our admissions criteria. Since the training is lab-based, we recommend a background that emphasizes hands-on laboratory courses. However, as long as you satisfy admission requirements, your bachelor’s degree in another discipline from a regionally accredited college/university is acceptable.

QUESTION: Are online courses acceptable to fulfill some of the prerequisites such as hematology, medical microbiology, and quantitative analysis?

ANSWER: Yes, online courses are acceptable.

QUESTION: I took general microbiology in college. Will this course meet the requirement?

ANSWER: No. You must have taken a course in medical microbiology (e.g., medical bacteriology, bacterial pathogenesis).

QUESTION: I have a bachelor's degree in biology but I do not have all of the specific prerequisites, in particular, hematology and quantitative analysis. My undergraduate program does not offer these, where can I take them?

ANSWER: A number of institutions offer these specific courses. Some are in person and some are offered online. Our CLS program does not recommend institutions or courses but a few to look into are those offered through UC Berkeley extension, UC San Diego extension, UC Davis extension, and several California State Universities such as, Long Beach, Dominguez Hills and San Diego.

Ultimately, it is up to Laboratory Field Services (LFS), the agency that grants CLS training licenses, to approve specific courses. It is always a good idea to check with LFS should you have specific questions regarding courses. We defer to the LFS decision as to prerequisite course acceptability.

QUESTION: I have a bachelor’s degree from another country. Am I eligible to apply?

ANSWER: Yes. However, you must meet additional admission requirements. Applicants with foreign (non-U.S.) degrees must have their original transcripts evaluated by an acceptable agency and have the evaluation sent directly to the training program. Refer to the information published by Laboratory Field Services as to transcript evaluation services that will be accepted. The evaluation must include a course-by-course identification of courses, credits and grades. Foreign-degree candidates must complete at least 30 semester units (45 quarter units) at a U.S. college or university in upper division science courses. If the applicant does not have U.S. citizenship, he/she must have permanent residency in the U.S. or DACA documentation.

QUESTION: I have an MD (or PhD) degree. Am I a qualified applicant for CLS training?

ANSWER: All candidates, regardless of credentials, must meet the same admissions criteria. If your credential is from another country, you must also meet the additional requirements stated above. Some institutions offer limited licensure CLS specialty programs, which provide training for specific laboratory disciplines. If you have an extensive background in a specialized category, you may be eligible for this type of training.

QUESTION: Will I receive a degree in clinical laboratory science after completing the training program?

ANSWER: No. The training program at UCI Medical Center is a post-baccalaureate certificate program. Graduates receive a certificate of completion, but the program does not award a degree.

QUESTION: Is it necessary to have experience working in a clinical laboratory?

ANSWER: Clinical laboratory work experience is not a requirement for admission. However, it is much to your benefit to obtain exposure to the CLS profession from the “bench” perspective. The clinical lab environment is quite different from that of a research lab or college laboratory course. These different laboratories may share certain methods and techniques, but working conditions are unique in each situation. Because CLS training does require a full-time, one-year commitment, it is best to see beforehand whether it really is to your liking. Opportunities to obtain such experience may come from volunteering in a clinical lab, or working as a phlebotomist, lab assistant or lab technician.

QUESTION: How competitive is the application process?

ANSWER: Admission to the program has become increasingly competitive. The number of applications we receive varies from year to year, but has been on an upward trend. Since our program only admits up to 6 students per year, we generally have more qualified applicants than available positions.

View Program Outcome Measures

Program Administrators

Medical Director

Luis M. de la Maza, MD, PhD

Program Director

Ellena Peterson, PhD, F(AAM), CLS, MT(ASCP)

All questions regarding the training program should be sent to