ASCP BOC 33 West Monroe Street, Suite 1600, Chicago, IL 60603 | www.ascp.org/boc | Revised: July 2023 | Page 1 of 15
MEDICAL LABORATORY SCIENTIST, MLS(ASCP)
INTERNATIONAL MEDICAL LABORATORY SCIENTIST, MLS(ASCP
i
)
EXAMINATION CONTENT GUIDELINE
EXAMINATION MODEL
The MLS(ASCP) and MLS(ASCP
i
) certification examination is composed of 100 questions given in a 2 hour 30 minute time
frame. All exam questions are multiple-choice with one best answer. The certification exam is administered using the
format of computer adaptive testing (CAT).
With CAT, when a person answers a question correctly, the next test question has a slightly higher level of difficulty. The
difficulty level of the questions presented to the examinee continues to increase until a question is answered incorrectly.
Then a slightly easier question is presented. In this way, the test is tailored to the individual’s ability level.
Each question in the test bank is calibrated for level of difficulty and is classified by content area. The content area aligns
with the examination specific content outline. The examinee must answer enough questions correctly to achieve a
measure above the pass point in order to successfully pass the certification examination. There is no set number of
questions one must answer to pass, nor is there a set percentage one must achieve to pass. If at the end of the exam the
examinee’s score is above the pass point, then he or she passes the exam.
EXAMINATION CONTENT AREAS
The MLS exam questions encompass different content areas within Medical Laboratory Science: Blood Banking, Urinalysis
and Other Body Fluids, Chemistry, Hematology, Immunology, Microbiology, and Laboratory Operations. Each of these
content areas comprise a specific percentage of the overall 100-question exam. The content areas and percentages are
described below:
CONTENT AREA
DESCRIPTION
EXAM
PERCENTAGE
BLOOD BANKING
Blood products, blood group systems, blood group immunology, physiology
and pathophysiology, serologic and molecular testing, transfusion practice
17 – 22%
URINALYSIS AND
OTHER BODY FLUIDS
Physical and chemical testing, microscopic analysis, physiology, disease
states
5 – 10%
CHEMISTRY
Carbohydrates, lipids, heme derivatives, enzymes, proteins and other
nitrogen-containing compounds, acid-base determinations (including blood
gases), electrolytes, endocrinology, vitamins and nutrition, therapeutic
drug monitoring, toxicology
17 – 22%
HEMATOLOGY
Physiology, disease states, laboratory testing, hemostasis (including
physiology, disease states, and laboratory determinations)
17 – 22%
IMMUNOLOGY
Principles of immunology, diseases of the immune system, transplantation,
infectious disease serology, serologic procedures, test results
5 – 10%
MICROBIOLOGY
Preanalytic procedures; analytic procedures for bacteriology; analytic
procedures for mycobacteriology, virology, parasitology, and mycology;
postanalytic procedures
17 – 22%
LABORATORY
OPERATIONS
Quality assessment/troubleshooting, safety, laboratory mathematics,
manual/automated methodology and instrumentation, basic management
principles, education principles
5 – 10%
For a more specific overview of the MLS exam, please refer to the CONTENT OUTLINE starting on page 2.
ASCP BOC 33 West Monroe Street, Suite 1600, Chicago, IL 60603 | www.ascp.org/boc | Revised: July 2023 | Page 2 of 15
MEDICAL LABORATORY SCIENTIST, MLSASCP)
INTERNATIONAL MEDICAL LABORATORY SCIENTIST, MLS(ASCP
i
)
EXAMINATION CONTENT OUTLINE
Examination questions, which are related to the subtest areas outlined below, may be both theoretical and/or procedural.
Theoretical questions measure skills necessary to apply knowledge, calculate results, and correlate patient results to
disease states. Procedural questions measure skills necessary to perform laboratory techniques and follow quality
assurance protocols. Additionally, regulatory questions are based on U.S. sources (e.g., AABB, FDA, CLIA).
NOTE ABOUT DONOR ELIGIBILITY QUESTIONS: the exam questions are based on current guidelines as of June 2023.
BLOOD BANKING
(17 – 22% of total exam)
I. BLOOD PRODUCTS
A. Donors
1. Qualification
2. Collection methods
3. Adverse reactions
4. Special donations (e.g., autologous)
B. Processing
1. Testing
2. Labeling
C. Storage
1. Anticoagulants/additives
2. Temperature requirements
3. Transportation
4. Properties of stored products
5. Expiration
D. Blood Components
1. Red blood cells
2. Cryoprecipitated AHF
3. Platelets
4. Plasma
5. Granulocytes
6. Leukocyte-reduced components
7. Frozen/deglycerolized red blood cells
8. Apheresis products
9. Fractionation products
10. Whole blood
11. Washed red blood cells
12. Irradiated components
E. Blood Component Quality Control
II. BLOOD GROUP SYSTEMS
A. Genetics
1. Basic
2. Molecular
3. Inheritance of blood groups
B. Biochemistry/Antigens
1. ABO
2. Lewis
3. Rh
4. MNS
5. P1PK/Globoside(P)
6. Ii
7. Kell
8. Kidd
9. Duffy
10. Lutheran
11. Antigens of high prevalence
12. Antigens of low prevalence
13. HLA
14. Platelet-specific
C. Role of Blood Groups in Transfusion
1. Immunogenicity
2. Antigen prevalence
III. BLOOD GROUP IMMUNOLOGY
A. Immune Response
1. Primary and secondary response
2. B and T cells, macrophages
3. Genetics
B. Immunoglobulins
1. Classes and subclasses
2. Structure
3. Biologic and physical properties
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C. Antigen-Antibody Interactions
1. Principles
2. Testing
a. Principles
b. Methods
D. Complement
1. Classical and alternative pathway
mechanisms
2. Biologic properties
IV. PHYSIOLOGY AND PATHOPHYSIOLOGY
A. Physiology of Blood
1. Circulation and blood volume
2. Composition and function of blood
a. Normal function
b. Abnormal physiology
3. Cell survival
4. Cell metabolism
B. Hemostasis and Coagulation
1. Coagulation factors and disorders
2. Platelet functions and disorders
C. Hemolytic Disease of the Fetus and Newborn
1. Pathophysiology
2. Detection
3. Treatment
4. Prevention
D. Anemias
1. Congenital and acquired
a. Pathophysiology
b. Detection
c. Treatment
2. Immune hemolytic anemias: warm, cold,
drug-induced
a. Pathophysiology
b. Detection
c. Treatment
E. Transplantation
1. Solid organ
2. Hematopoietic progenitor cell (HPC)
V. SEROLOGIC AND MOLECULAR TESTING
A. Routine Tests
1. Blood grouping tests
2. Compatibility tests
a. Antibody detection
b. Crossmatch
3. Antibody identification/clinical significance
4. Direct antiglobulin testing
B. Reagents
1. Antiglobulin sera
2. Blood grouping sera
3. Reagent red cells
C. Application of Special Tests and Reagents
1. Enzymes
2. Enhancement media
3. Lectins
4. Adsorptions
5. Elutions
6. Titrations
7. Cell separations
8. ELISA
9. Molecular techniques
10. Neutralization/inhibition
11. Use of thiol reagents
12. Immunofluorescence
13. Solid phase
14. Column agglutination test
15. Chloroquine diphosphate
16. EDTA glycine-acid
D. Leukocyte/Platelet Testing
1. Cytotoxicity
2. Platelet testing
E. Quality Assurance
1. Blood samples
2. Reagents
3. Test procedures
VI. TRANSFUSION PRACTICE
A. Indications for Transfusion
B. Component Therapy
C. Adverse Effects of Transfusion
1. Immunologic reactions
2. Nonimmunologic reactions
3. Transfusion-transmitted diseases
D. Apheresis and Extracorporeal Circulation
E. Blood Administration and Patient Blood
Management
ASCP BOC 33 West Monroe Street, Suite 1600, Chicago, IL 60603 | www.ascp.org/boc | Revised: July 2023 | Page 4 of 15
URINALYSIS AND BODY FLUIDS
(5 – 10% of total exam)
I. URINALYSIS
A. Physical
1. Color and clarity
2. Specific gravity/osmolality
B. Chemical
1. Reagent strip
2. Confirmatory tests
C. Microscopic
1. Cells
2. Casts
3. Crystals
4. Microorganisms
5. Contaminants
6. Artifacts
D. Renal Physiology
E. Disease States
II. BODY FLUIDS (e.g., CSF, Amniotic, Synovial,
Serous, Semen, Feces)
A. Physical
B. Chemical
C. Microscopic
D. Physiology
E. Disease States
CHEMISTRY
(17 – 22% of total exam)
I. GENERAL CHEMISTRY
A. Carbohydrates
1. Biochemical theory and physiology
a. Metabolic pathways
b. Normal and abnormal states
c. Physical and chemical properties
2. Test procedures
a. Principles
b. Special precautions, specimen
collection and processing,
troubleshooting, and interfering
substances
c. Tolerance testing
d. Glycated proteins
3. Test result interpretation
4. Disease state correlation
B. Lipids
1. Biochemical theory and physiology
a. Metabolic pathways
b. Normal and abnormal states
c. Physical and chemical properties
1) Lipoproteins
2) Phospholipids
3) Triglycerides
4) Cholesterol
5) Apolipoproteins
2. Test procedures
a. Principles
b. Special precautions, specimen
collection and processing,
troubleshooting, and interfering
substances
3. Test result interpretation
4. Disease state correlation
C. Heme Derivatives
1. Biochemical theory and physiology
a. Metabolic pathways
b. Normal and abnormal states
c. Physical and chemical properties
1) Hemoglobin
2) Bilirubin
3) Urobilinogen
4) Myoglobin
5) Porphyrins
2. Test procedures
a. Principles
b. Special precautions, specimen
collection and processing,
troubleshooting, and interfering
substances
3. Test result interpretation
4. Disease state correlation
II. PROTEINS AND ENZYMES
A. Enzymes
1. Biochemical theory and physiology
a. Metabolic pathways
b. Normal and abnormal states
c. Physical and chemical properties
1) LD
2) CK
3) AST/ALT
4) GGT
5) Lipase
ASCP BOC 33 West Monroe Street, Suite 1600, Chicago, IL 60603 | www.ascp.org/boc | Revised: July 2023 | Page 5 of 15
6) Amylase
7) Alkaline phosphatase
8) Angiotensin converting enzyme
2. Test procedures
a. Principles
b. Special precautions, specimen
collection and processing,
troubleshooting, and interfering
substances
3. Test result interpretation
4. Disease state correlation
B. Proteins and Other Nitrogen-Containing
Compounds
1. Biochemical theory and physiology
a. Metabolic pathways
b. Normal and abnormal states
c. Physical and chemical properties
1) Proteins
2) Amino acids
3) Urea
4) Uric acid
5) Creatinine
6) Ammonia
7) Tumor markers
8) Cardiac markers
2. Test procedures
a. Principles
b. Special precautions, specimen
collection and processing,
troubleshooting, and interfering
substances
c. Clearances
3. Test result interpretation
4. Disease state correlation
III. ACID-BASE, BLOOD GASES AND ELECTROLYTES
A. Acid-Base Determinations (Including
Blood Gases)
1. Biochemical theory and physiology
a. Henderson-Hasselbach equation
b. pH and H
+
ion concentration
c. CO
2
and O
2
transport
d. Normal and abnormal states
2. Test procedures
a. Analytical principles
b. Special precautions, specimen
collection and processing,
troubleshooting, and interfering
substances
3. Test result interpretation
4. Disease state correlation
B. Electrolytes
1. Biochemical theory and physiology
a. Sodium, potassium, chloride, CO
2
,
bicarbonate
b. Calcium, magnesium, phosphorus, iron,
TIBC
c. Trace elements
d. Normal and abnormal states
2. Test procedures
a. Principles
b. Special precautions, specimen
collection and processing,
troubleshooting, and interfering
substances
3. Calculations (osmolality, anion gap)
4. Test result interpretation
5. Disease state correlation
IV. SPECIAL CHEMISTRY
A. Endocrinology
1. Biochemical theory and physiology
a. Metabolic pathways
b. Normal and abnormal states
c. Mechanism of action
d. Physical and chemical properties
1) Steroid hormones (e.g., cortisol,
estrogen, hCG)
2) Peptide hormones (e.g., insulin,
prolactin)
3) Thyroid hormones
4) Catecholamines
2. Test procedures
a. Principles
1) Fluorescence
2) Immunoassay
b. Special precautions, specimen
collection and processing,
troubleshooting, and interfering
substances
c. Stimulation/suppression tests
3. Test result interpretation
4. Disease state correlation
ASCP BOC 33 West Monroe Street, Suite 1600, Chicago, IL 60603 | www.ascp.org/boc | Revised: July 2023 | Page 6 of 15
B. Vitamins and Nutrition
1. Biochemical theory and physiology
a. Metabolism and action
b. Normal and abnormal states
c. Properties
2. Test procedures
a. Principles
b. Special precautions, specimen
collection and processing,
troubleshooting, and interfering
substances
3. Test result interpretation
4. Disease state correlation
C. Therapeutic Drug Monitoring
1. Pharmacokinetics
a. Therapeutic states
b. Toxic states
c. Metabolism and excretion
2. Chemical and physical properties
a. Aminoglycosides (e.g., gentamicin)
b. Cardioactive (e.g., digoxin)
c. Anticonvulsants (e.g., phenobarbital)
d. Antidepressants (e.g., lithium)
e. Immunosuppressants (e.g., tacrolimus)
3. Test procedures
a. Principles
1) Immunoassay
b. Special precautions, specimen
collection and processing,
troubleshooting, and interfering
substances
4. Test result interpretation
5. Disease state correlation
D. Toxicology
1. Toxicokinetics
a. Toxic effects, signs and symptoms
b. Metabolism and excretion
2. Chemical and physical properties
a. Alcohols
b. Heavy metals (e.g., lead)
c. Analgesics (e.g., acetaminophen)
d. Drugs of abuse
3. Test procedures
a. Principles
1) Immunoassay
2) Enzymatic methods
b. Special precautions, specimen
collection and processing, troubleshooting,
and interfering substances
4. Test result interpretation
5. Disease state correlation
HEMATOLOGY
(17 – 22% of total exam)
I. HEMATOLOGY PHYSIOLOGY (to include blood,
body fluids, and bone marrow)
A. Production
B. Destruction
C. Function
II. HEMATOLOGY DISEASE STATES
A. Erythrocytes
1. Anemia
a. Microcytic
1) Iron deficiency
2) Thalassemia
3) Sideroblastic
4) Chronic inflammation
b. Normocytic
1) Hereditary hemolytic
2) Acquired hemolytic
3) Hypoproliferative
4) Acute hemorrhage
c. Macrocytic
1) Megaloblastic
2) Non-megaloblastic
d. Hemoglobinopathies
2. Erythrocytosis
a. Relative
b. Absolute
B. Leukocytes (WHO classification)
1. Benign leukocyte disorders
a. Myeloid
b. Lymphoid
2. Myeloid neoplasia
a. Acute leukemia
b. Myelodysplastic syndromes
c. Myeloproliferative neoplasms
3. Lymphoid neoplasia
a. Acute leukemia
b. Chronic leukemia/lymphoma
c. Plasma cell dyscrasias
4. Hereditary anomalies
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C. Platelets
1. Quantitative abnormalities
a. Thrombocytopenia
1) Increased destruction (e.g., ITP,
TTP, HIT)
2) Decreased production
3) Pseudothrombocytopenia
b. Thrombocytosis
2. Qualitative defects
a. von Willebrand disease
b. Bernard-Soulier syndrome
c. Glanzmann thrombasthenia
III. HEMATOLOGY LABORATORY TESTING
A. Cell Counts (to include blood and body fluids)
1. Manual
2. Automated
3. Reticulocytes
4. Spurious results
B. Differentials and Morphology Evaluation (to
include blood and body fluids)
C. Hemoglobin
1. Quantitative
2. Qualitative
a. Electrophoresis
b. HPLC
c. Sickle solubility
D. Hematocrit
E. Indices
F. Hemolytic Indicators (e.g., haptoglobin, LD)
G. Special Stains
1. Esterase
2. Myeloperoxidase
3. Prussian blue
4. Kleihauer-Betke
H. Other Studies
1. ESR
2. G-6-PD
3. Heinz body
I. Flow Cytometry Immunophenotyping
1. Leukemia
2. Lymphoma
3. Lymphocyte subsets
4. PNH
J. Molecular and Cytogenetic Testing
1. Recurring cytogenetic abnormalities (WHO
classification)
2. BCR/ABL1
3. JAK2
IV. HEMOSTASIS
A. Physiology
1. Coagulation pathways
2. Fibrinolytic pathway
3. Vascular system
B. Disease States
1. Coagulation factor deficiencies
a. Acquired
b. Hereditary
2. Inhibitors
3. Fibrinolytic system
4. Hypercoagulable states
5. DIC
C. Laboratory Determinations
1. PT/INR
2. APTT
3. Fibrinogen
4. D-dimer
5. Thrombin time
6. Mixing studies
7. Platelet function (e.g., PFA)
8. Inhibitor assays
9. Factor assays
10. von Willebrand assays
11. Platelet aggregation
12. Thromboelastography
13. Hypercoagulability assessment
a. Assays (e.g., lupus anticoagulant,
protein S, protein C, HIT studies)
b. Molecular (e.g., factor V Leiden,
prothrombin 20210)
14. Anti-Xa
15. Direct thrombin inhibitors
16. Heparin neutralization
ASCP BOC 33 West Monroe Street, Suite 1600, Chicago, IL 60603 | www.ascp.org/boc | Revised: July 2023 | Page 8 of 15
IMMUNOLOGY
(5 – 10% of total exam)
I. PRINCIPLES OF IMMUNOLOGY
A. Immune System Physiology
1. Primary and secondary response
2. B and T cells, macrophages
3. Genetics
B. Immunoglobulins
1. Classes and subclasses
2. Structure
3. Biologic and physical properties
C. Antigen-Antibody Interactions
1. Principles
2. Testing
a. Principles
b. Methods
D. Complement
1. Classical and alternative pathway
mechanisms
2. Biologic properties
II. DISEASES OF THE IMMUNE SYSTEM
A. Autoimmunity
1. Systemic (e.g., SLE)
2. Organ-specific (e.g., Graves disease)
B. Hypersensitivity
1. I, II, III, IV
C. Immunoproliferative Diseases
1. Monoclonal gammopathies (e.g., plasma
cell myeloma, Waldenström
macroglobulinemia)
D. Immunodeficiency
1. Hereditary (e.g., SCID)
2. Acquired (e.g., HIV)
III. TRANSPLANTATION
A. Graft-versus-host Disease
B. HLA Typing
C. Tumor Immunology
IV. INFECTIOUS DISEASE SEROLOGY
A. Clinical Significance and Epidemiology of Viral
Pathogens (e.g., hepatitis [A, B, C], EBV, HIV,
CMV, rubella, measles)
B. Stages of Infection of Treponema pallidum and
Borrelia burgdorferi
C. Tuberculosis Infection (e.g., interferon-gamma
release assay, PPD)
V. SEROLOGIC PROCEDURES
A. ANA
B. Thyroid Antibodies
C. Rheumatoid Factor
D. Labeled Immunoassays (e.g., ELISA)
E. Nontreponemal Syphilis Testing (e.g., RPR)
F. Treponemal Syphilis Testing (e.g., MHATP)
G. Cytokine Testing
H. Immunofluorescence
VI. TEST RESULTS
A. Interpretation
B. Confirmatory Testing
C. Disease State Correlation
MICROBIOLOGY
(17 – 22% of total exam)
I. PREANALYTIC PROCEDURES
A. Specimen Collection and Transport
1. Patient identification and specimen labeling
2. Specimen collection
3. Specimen transport systems and conditions
for all organisms
B. Specimen Processing
1. Specimen prioritization and rejection
criteria
2. Biosafety cabinet and personal protective
equipment
3. Specimen preparation methods and
applications
4. Media
5. Inoculation of media
6. Incubation conditions (e.g., temperature,
atmosphere, duration)
7. Preparation methods for slides used for
stains
C. Stains: Procedure, Principle, and Interpretation
1. Gram
2. Acid-fast
3. Modified acid-fast
4. KOH and calcofluor-white
5. Trichrome
6. Giemsa
7. Acridine orange
ASCP BOC 33 West Monroe Street, Suite 1600, Chicago, IL 60603 | www.ascp.org/boc | Revised: July 2023 | Page 9 of 15
II. ANALYTIC PROCEDURES FOR BACTERIOLOGY
A. Blood and Bone Marrow
1. Specimen sources (e.g., peripheral,
intravenous catheters)
2. Continuous-monitoring systems
3. Rapid identification/resistance detection
methods
4. Species comprising skin flora and clinical
significance
5. Colony morphology and identification of
major pathogens (e.g., Staphylococcus
aureus, other Staphylococcus spp. including
coagulase-negative staphylococci, beta-
hemolytic streptococci, Enterococcus spp.,
Candida spp., Streptococcus pneumoniae,
Acinetobacter baumannii,
Enterobacteriaceae, Pseudomonas spp.)
6. Common agents of endocarditis
7. Agents of bone marrow infection (e.g.,
Brucella spp., Salmonella spp.)
8. Organism pathogenicity (e.g., etiology,
transmission, virulence mechanisms)
B. Cerebrospinal Fluid
1. Specimen sources (e.g., lumbar puncture,
shunt, reservoir)
2. Colony morphology and identification of
major pathogens associated with acute
meningitis (e.g., Streptococcus pneumoniae,
Haemophilus influenzae, Neisseria
meningitidis, Escherichia coli, Listeria
monocytogenes, Enterobacteriaceae,
Staphylococcus aureus, beta-hemolytic
streptococci)
3. Common agents of shunt infections (e.g.,
other Staphylococcus spp. including
coagulase-negative staphylococci,
Corynebacterium spp., Propionibacterium
spp., Cutibacterium spp.)
4. Correlation with other laboratory results
(e.g., glucose, protein, cell count)
5. Direct detection and molecular methods
6. Organism pathogenicity (e.g., etiology,
transmission, virulence mechanisms)
C. Body Fluids from Normally Sterile Sites
1. Specimen sources (e.g., pleural, peritoneal,
pericardial, vitreous and aqueous humor,
synovial, amniotic)
2. Indigenous organisms associated with
mucosal surfaces and skin
3. Colony morphology and identification of
major pathogens (e.g., Streptococcus
pneumoniae, Haemophilus influenzae,
Neisseria spp., Escherichia coli, Listeria
monocytogenes, Enterobacteriaceae,
Staphylococcus aureus, beta-hemolytic
streptococci, Enterococcus spp.,
Pseudomonas aeruginosa, Acinetobacter
spp., Clostridium perfringens, Bacteroides
fragilis group)
4. Molecular methods
5. Organism pathogenicity (e.g., etiology,
transmission, virulence mechanisms)
D. Lower Respiratory
1. Specimen sources (e.g., sputum,
endotracheal aspirate, bronchoalveolar
lavage, bronchial wash, bronchial brush)
2. Significance of quantitative and semi-
quantitative reporting of results
3. Species comprising oral flora colony and
Gram stain morphology
4. Colony morphology and identification of
major pathogens
5. Direct detection and molecular methods
(e.g., Streptococcus pyogenes, Bordetella
pertussis)
6. Organism pathogenicity (e.g., etiology,
transmission, virulence mechanisms)
E. Upper Respiratory
1. Specimen sources (e.g., throat,
nasopharynx, middle ear, sinus)
2. Indigenous flora colony and Gram stain
morphology
3. Colony morphology and identification of
major pathogens
4. Direct detection and molecular methods
(e.g., Streptococcus pyogenes, Bordetella
pertussis)
5. Organism pathogenicity (e.g., etiology,
transmission, virulence mechanisms)
ASCP BOC 33 West Monroe Street, Suite 1600, Chicago, IL 60603 | www.ascp.org/boc | Revised: July 2023 | Page 10 of 15
F. Gastrointestinal
1. Colony morphology and identification of
major pathogens (e.g., Salmonella spp.,
Shigella spp., toxigenic Escherichia coli,
Campylobacter spp., Vibrio spp., Yersinia
enterocolitica, Aeromonas spp.,
Plesiomonas shigelloides)
2. Direct detection and molecular methods
(e.g., Clostridioides difficile, Shiga toxin)
3. Serotyping of Escherichia coli, Salmonella
spp., and Shigella spp.
4. Organism pathogenicity (e.g., etiology,
transmission, virulence mechanisms)
5. Detection methods for Helicobacter pylori
G. Skin, Soft Tissue, and Bone
1. Specimen sources (e.g., wound, abscess,
biopsy)
2. Indigenous flora colony and Gram stain
morphology
3. Colony morphology and identification of
major pathogens
4. Organism pathogenicity (e.g., etiology,
transmission, virulence mechanisms)
H. Genital Tract
1. Specimen sources (e.g., vaginal, cervical,
urethral, endocervical)
2. Indigenous organisms colony and Gram
stain morphology
3. Methods for detection of pathogens
associated with vaginitis (e.g., Trichomonas
vaginalis, Candida spp., bacterial vaginosis)
4. Culture and/or molecular detection (e.g.,
Neisseria gonorrhoeae, Chlamydia
trachomatis, Streptococcus agalactiae, and
Mycoplasma spp.)
5. Organism pathogenicity (e.g., etiology,
transmission, virulence mechanisms)
I. Urine
1. Specimen sources (e.g., mid-stream clean-
catch, catheterized, suprapubic,
nephrostomy)
2. Colony morphology and identification of
major urinary pathogens (e.g.,
Enterobacteriaceae, Enterococcus spp.,
Streptococcus agalactiae, Candida spp.,
Staphylococcus saprophyticus)
3. Correlation of colony counts with clinical
significance
4. Correlation of culture with urinalysis results
J. Identification Methods (Theory, Interpretation,
and Application)
1. Colony morphology
2. Rapid tests used for presumptive
identification (e.g., coagulase, catalase,
oxidase, indole, PYR)
3. Conventional biochemical identification
(e.g., X and V factors, Neisseria
carbohydrate utilization)
4. Commercial kits
5. Automated methods
6. MALDI-TOF MS
7. Multiplex molecular methods
8. Sequencing (e.g., 16S)
K. Antimicrobial Susceptibility Testing and
Antibiotic Resistance
1. Method, theory, interpretation, and
application
2. Phenotypic detection of resistance (e.g.,
beta-lactamase, ESBL, inducible clindamycin
resistance, carbapenamases)
3. Mechanisms of action of major antibiotic
classes
4. Detection of genetic determinants of
resistance (e.g., mecA, vanA, bla
KPC
)
5. Intrinsic resistance patterns for common
species
L. MRSA/MSSA, VRE, ESBL/CRE Screening
1. Specimen sources
2. Culture methods
3. Molecular methods
M. BSL-3 Pathogens and Select Agents
(Bioterrorism)
1. Specimen sources (e.g., blood, sputum,
tissue, lymph node)
2. Colony morphology and rapid tests used for
presumptive identification (e.g., Bacillus
anthracis, Yersinia pestis, Brucella spp.,
Francisella tularensis)
3. Role of regional laboratory and Laboratory
Response Network
4. Organism pathogenicity (e.g., etiology,
transmission, virulence mechanisms)
ASCP BOC 33 West Monroe Street, Suite 1600, Chicago, IL 60603 | www.ascp.org/boc | Revised: July 2023 | Page 11 of 15
III. ANALYTIC PROCEDURES FOR
MYCOBACTERIOLOGY, VIROLOGY,
PARASITOLOGY, AND MYCOLOGY
A. Mycobacteriology and Nocardia spp.
1. Specimen sources (e.g., lower respiratory,
blood, soft tissue)
2. Major pathogens and disease states (e.g.,
etiology, epidemiology, transmission)
3. Acid-fast reaction, colony morphology, and
growth characteristics
4. Identification methods (e.g., probes,
sequencing, MALDI-TOF MS)
5. Direct detection by molecular methods
6. Antimicrobial therapy
7. Organism pathogenicity (e.g., etiology,
transmission, virulence mechanisms)
B. Virology
1. Specimen sources
2. Major pathogens and disease states (e.g.,
etiology, epidemiology, transmission)
3. Direct detection of pathogens
C. Parasitology
1. Specimen sources (e.g., stool, respiratory,
blood, tissue)
2. Major pathogens and disease states (e.g.,
etiology, epidemiology, transmission)
3. Microscopic and macroscopic identification
4. Direct and molecular detection
D. Mycology
1. Specimen sources
2. Major pathogens and disease states (e.g.,
etiology, epidemiology, transmission)
3. Colony morphology and growth
characteristics of major pathogens (e.g.,
temperature, growth rate, length of
incubation)
4. Microscopic identification of major
pathogens
5. Direct and molecular detection
6. Other identification methods (e.g.,
biochemical, automated methods, MALDI-
TOF MS)
IV. POSTANALYTIC PROCEDURES
A. Documentation Practices
B. Urgent and Critical Value Reporting
C. Result Review and Autoverification
D. Issuing Corrected Reports
E. Reporting to Infection Control/Prevention and
Public Health
LABORATORY OPERATIONS
(5 – 10% of total exam)
I. QUALITY ASSESSMENT/TROUBLESHOOTING
A. Preanalytical, Analytical, Postanalytical
B. Quality Control
C. Point-of-care Testing (POCT)
D. Compliance
E. Regulation (e.g., proficiency testing,
competency assessment, accreditation
standards)
II. SAFETY
A. Safety Programs and Practices
1. Prevention of infection with bloodborne
pathogens
2. Use of personal protective equipment (PPE)
3. Safe work practices
4. Packaging and transportation of specimens
and microorganisms
5. Safety data sheets (SDS) for chemicals and
reagents
B. Emergency Procedures (e.g., needlesticks,
splashes to mucous membranes, fire)
III. LABORATORY MATHEMATICS
A. Concentration, Volume, and Dilutions
B. Molarity, Normality
C. Standard Curves
D. Mean, Median, Mode, and Confidence Intervals
E. Sensitivity, Specificity, and Predictive Value
ASCP BOC 33 West Monroe Street, Suite 1600, Chicago, IL 60603 | www.ascp.org/boc | Revised: July 2023 | Page 12 of 15
IV. MANUAL/AUTOMATED METHODOLOGY AND
INSTRUMENTATION
A. Basic Laboratory Equipment
B. Spectrophotometry and Photometry
C. Mass Spectrometry
D. Osmometry
E. Electrophoresis
F. Chromatography
G. Electrochemistry
H. Fluorometry
I. Nephelometry
J. Flow Cytometry
K. Molecular Methods
L. Automated Microbiology Processors
M. Hematology Instrumentation
V. BASIC MANAGEMENT PRINCIPLES
VI. EDUCATION PRINCIPLES
Examples provided (as indicated by e.g.) are not limited
to those listed.
All Board of Certification examinations use
conventional and SI units for results and reference
ranges.
ASCP BOC 33 West Monroe Street, Suite 1600, Chicago, IL 60603 | www.ascp.org/boc | Revised: July 2023 | Page 13 of 15
THE EXAMINEE IS EXPECTED TO KNOW THESE ADDITIONAL CALCULATIONS AND REFERENCE RANGES:
CALCULATIONS
- % Transferrin saturation/UIBC/TIBC
- Unconjugated/indirect bilirubin
- LDL/Friedewald equation/non-HDL
- A/G ratio
- Timed urine calculations
- Creatinine clearance calculations
- Beer’s law
- Corrected WBC counts when > 10 nRBCs present
- Manual hemocytometer counts
- Red blood cell indices (e.g., MCV, MCH, MCHC)
- Absolute cell counts given the relative values (e.g., WBCs, reticulocytes)
REFERENCE RANGES (COMBINED MALE AND FEMALE)
CHEMISTRY REFERENCE RANGES
Conventional Units
SI Units
Sodium
136 – 145 mmol/L
136 – 145 mmol/L
Potassium
3.5 – 5.1 mmol/L
3.5 – 5.1 mmol/L
Chloride
98 – 107 mmol/L
98 – 107 mmol/L
Total CO
2
22 – 33 mmol/L
22 – 33 mmol/L
Creatinine
0.8 – 1.2 mg/dL
71 – 106 µmol/L
Blood urea nitrogen (BUN)
6 – 20 mg/dL
2.1 – 7.1 mmol/L
Glucose (fasting)
74 – 100 mg/dL
4.1 – 5.6 mmol/L
Hemoglobin A
1C
< 5.7%
< 39 mmol/mol
Haptoglobin
30 – 200 mg/dL
0.3 – 2.0 g/L
Arterial blood gases
pH
7.35 – 7.45
7.35 – 7.45
pCO
2
35 – 44 mmHg
4.7 – 5.9 kPa
pO
2
> 80 mmHg
> 10.6 kPa
O
2
saturation
> 95%
> 95%
HCO
3
-
(bicarbonate)
23 – 29 mmol/L
23 – 29 mmol/L
HEMATOLOGY REFERENCE RANGES
SI Units
RBC
4.00 – 6.00 x 10
12
/L
HGB
120 – 180 g/L
HCT
0.35 – 0.50 L/L
MCV
76 – 100 fL
MCH
26 – 34 pg
MCHC
320 – 360 g/L
ASCP BOC 33 West Monroe Street, Suite 1600, Chicago, IL 60603 | www.ascp.org/boc | Revised: July 2023 | Page 14 of 15
RDW
0.115 – 0.145
Reticulocytes (absolute)
Reticulocytes (relative)
20 – 115 x 10
9
/L
0.005 – 0.025
nRBCs
0 nRBC/100 WBC
Platelets
150 – 450 x 10
9
/L
WBC (Total)
3.6 – 10.6 x 10
9
/L
Neutrophils (absolute)
Neutrophils (relative)
1.7 – 7.5 x 10
9
/L
0.50 – 0.70
Lymphocytes (absolute)
Lymphocytes (relative)
1.0 – 3.2 x 10
9
/L
0.18 – 0.42
Monocytes (absolute)
Monocytes (relative)
0.1 – 1.3 x 10
9
/L
0.02 – 0.11
Eosinophils (absolute)
Eosinophils (relative)
0 – 0.3 x 10
9
/L
0.01 – 0.03
Basophils (absolute)
Basophils (relative)
0 – 0.2 x 10
9
/L
0.00 – 0.02
BODY FLUID REFERENCE RANGES
Conventional Units
SI Units
Cerebrospinal Fluid (CSF)
WBC and RBC
0 – 5/μL
0 – 5 x 10
6
/L
Glucose
50 – 80 mg/dL
2.8 – 4.4 mmol/L
Protein
15 – 45 mg/dL
150 – 450 mg/L
Seminal Fluid
Liquefaction
30 – 60 minutes
30 – 60 minutes
WBC
< 1 x 10
6
/mL
< 1 x 10
9
/L
Volume
2 – 5 mL
2 – 5 mL
pH
7.2 – 8.0
7.2 – 8.0
Motility
> 50% within 1 hour
> 50% within 1 hour
Sperm concentration
> 20 x 10
6
/mL
> 20 x 10
9
/L
Morphology
> 30% normal forms
> 30% normal forms
Urine
Specific gravity
1.003 – 1.035
1.003 – 1.035
pH
4.5 – 8.0
4.5 – 8.0
Protein
< 10 mg/dL, trace, or
negative
< 0.1 g/L, trace, or
negative
Bilirubin
negative
negative
Blood
negative
negative
Glucose
≤ 15 mg/dL or negative
≤ 0.8 mmol/L or negative
Nitrite
negative
negative
Leukocyte esterase
negative
negative
Urobilinogen
< 1.0 EU
< 17.0 μmol/L
ASCP BOC 33 West Monroe Street, Suite 1600, Chicago, IL 60603 | www.ascp.org/boc | Revised: July 2023 | Page 15 of 15
Ketones
< 5 mg/dL or negative
< 0.5 mmol/L or negative
Microscopic
RBC
0 – 3/HPF
0 – 3/HPF
WBC
0 – 8/HPF
0 – 8/HPF
Casts
0 – 2 hyaline/LPF
0 – 2 hyaline/LPF
Epithelial cells
0 – 5/HPF
0 – 5/HPF
All values on the MLS exam can be interpreted using the reference ranges above. These reference ranges will not be given
on the exam. Other reference ranges will be provided as needed on the exam.
END OF CONTENT GUIDELINE