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Key Facts: MLS Exam
210
Total Items
AMT MLS
3.5 hrs
Exam Time
AMT
$245
Exam Fee
AMT
2023
MT → MLS rebrand
AMT aligned with ASCP MLS
70
Scaled Passing Score
AMT Candidate Handbook
45 days
Retake Wait
AMT retesting policy
AMT MLS is the bachelor's-level generalist clinical lab credential (formerly AMT MT, rebranded 2023, aligned with ASCP MLS branding). 210 items, 3.5 hours, $245. Master Westgard QC rules, ABO/Rh and antibody screen workflow, acute hemolytic transfusion reaction protocol, Strep/Staph identification, Friedewald LDL formula, and HER2 IHC/FISH cascade.
Sample MLS Practice Questions
Try these sample questions to test your MLS exam readiness. Each question includes a detailed explanation. Start the interactive quiz above for the full 128+ question experience with AI tutoring.
1A Levey-Jennings chart shows a single control value falling more than 3 standard deviations from the mean. Which Westgard rule is violated?
2Which Westgard rule indicates systematic shift when 10 consecutive control values fall on one side of the mean?
3A waived complexity test under CLIA requires which of the following?
4A reference range for hemoglobin in an adult male is best represented by:
5A patient has MCV of 70 fL with low ferritin and elevated TIBC. The most likely diagnosis is:
6A bone marrow shows >20% promyelocytes with Auer rods and faggot cells. The patient develops DIC. The most likely diagnosis is:
7The Philadelphia chromosome t(9;22) producing the BCR-ABL fusion is most associated with:
8Which of the following extends the prothrombin time (PT) but not the partial thromboplastin time (PTT)?
9A mixing study shows correction of prolonged PTT after 1:1 mixing with normal plasma. This indicates:
10Anti-A and anti-B antibodies in human serum are typically of which immunoglobulin class?
About the MLS Exam
AMT bachelor's-level generalist clinical laboratory credential. AMT retired the legacy "MT" (Medical Technologist) designation in 2023 and now uses MLS. The current outline has nine domains: general laboratory, chemistry, hematology, coagulation and hemostasis, immunology and serology, immunohematology, blood banking and transfusion, microbiology, and urinalysis and body fluids.
Questions
210 scored questions
Time Limit
3.5 hours
Passing Score
70 on a 0-100 scale
Exam Fee
$245 (AMT)
MLS Exam Content Outline
General Laboratory
Quality systems, regulations, safety, instrumentation, specimen handling, and laboratory operations
Chemistry
Clinical chemistry methods, calculations, quality, and interpretation across organ systems
Hematology
Cell counts and morphology, anemias, leukocyte disorders, hemoglobinopathies, and instrumentation
Coagulation and Hemostasis
Hemostasis pathways, coagulation tests, disorders, anticoagulants, and interpretation
Immunology and Serology
Immune principles, testing methods, infectious serology, and autoimmune testing
Immunohematology
Blood groups, antibody testing, compatibility, and hemolytic disease
Blood Banking and Transfusion
Donor and component selection, preparation and storage, transfusion, and reaction investigation
Microbiology
Bacteriology, mycology, parasitology, virology, susceptibility, and molecular methods
Urinalysis and Body Fluids
Physical, chemical, and microscopic urinalysis and other body-fluid analysis
How to Pass the MLS Exam
What You Need to Know
- Passing score: 70 on a 0-100 scale
- Exam length: 210 questions
- Time limit: 3.5 hours
- Exam fee: $245
Keys to Passing
- Complete 500+ practice questions
- Score 80%+ consistently before scheduling
- Focus on highest-weighted sections
- Use our AI tutor for tough concepts
MLS Study Tips from Top Performers
Frequently Asked Questions
What are the Westgard QC rules?
Westgard multi-rule QC: 1-3s (1 control >3SD = REJECT); 1-2s (warning, trigger further evaluation); 2-2s (2 consecutive same side >2SD = reject, systematic error); R-4s (range >4SD between controls = random error); 4-1s (4 consecutive >1SD same side = bias); 10-x (10 consecutive same side of mean = shift). Distinguish random vs systematic error to guide troubleshooting.
How is acute hemolytic transfusion reaction managed?
Most often ABO incompatibility from clerical error. Symptoms: fever, chills, back/flank pain, hemoglobinuria, hypotension, DIC. STOP transfusion immediately, maintain IV access with NS, send remaining unit + post-transfusion blood/urine to blood bank, monitor renal function, supportive care. Investigate cause (recheck sample identity, repeat ABO/Rh on pre/post samples, DAT). Document and report per facility policy.
What is the Friedewald formula?
LDL-C = Total Cholesterol − HDL-C − (Triglycerides / 5), valid only when triglycerides <400 mg/dL. Above 400, Friedewald becomes unreliable and direct LDL measurement is required. Newer Martin-Hopkins formulas use an adjustable triglyceride factor.
How should I study for AMT MLS?
Plan 120-200 hours over 16-20 weeks. Follow AMT's nine-domain, 210-item outline. General Laboratory (44), Chemistry (38), and Hematology (32) are largest; Immunohematology (22), Microbiology (26), and the four smaller domains complete the blueprint.
What is the AMT MLS retake policy?
AMT requires at least 45 days between attempts and allows no more than four attempts for one certification. Each retake requires a new fee.