Skip directly to site content Skip directly to page options Skip directly to A-Z link Skip directly to A-Z link Skip directly to A-Z link

Preferred Usage

affect, effect

affect (v), to influence

affect (n), subjective aspect of an emotion (psychological studies)

effect (v), to bring about or initiate

effect (n), result or outcome

age designations



neonate or newborn

birth to 1 month


1 month to 1 year


2–12 years


5–18 years


13–19 years


13–17 years


>18 years

childbearing age

15–44 years


(determined by the author)

Alaska native, Alaska Native

Alaska native: anyone who was born and raised in Alaska, regardless of cultural background.

Alaska Native: a person who has origins in any of the original peoples of the area that is now Alaska and who maintains cultural identification through tribal affiliation or community recognition

American Indians, Native Americans

An American Indian is a person whose origins are in any of the original people of North (except Alaska), Central, or South America and who maintains cultural identification through tribal affiliation or community attachment. Whenever possible, specify the nation or people (e.g., Navajo, Anishinabe, Inuit) rather than using the more general term.  Either American Indians or Native Americans is acceptable, although Native Americans is preferred. Usage of either term is at the author’s discretion.

among, between

Among always applies to >2 objects.

Between literally applies to only 2 objects but may be used with >2 when each is treated individually, as in “a treaty between 3 powers.”


Avoid. In most cases, either and or or is correct. When a choice cannot be made, use “X, Y, or both.”

antibodies to, antibodies against

Although somewhat redundant, use antibodies against.

antigen, T- and t-

See t-antigen.

based on, on the basis of

Based on is often erroneously used to mean on the basis of. Correctly used, it follows forms of the verb to be.

The calculations were based on the following results.


Use BCE (“before the Common Era”) instead of BC (“before Christ”).

If inclusive dates are used with BCE, the higher numbered year comes first, and the second number should be given in full to avoid confusion (e.g., “375–330 BCE”). If inclusive dates carry over into CE ((“of the Common Era”), use an en dash between the dates (e.g., 11 BCE–20 CE).

The abbreviation should be set in small caps.


The procedure of removing and examining tissue, cells, or fluids from the living body. Observations are made on the biopsy specimen, not on the biopsy itself. Biopsy is a noun; do not use as a verb.

Black, African American

Use of either term is acceptable at the author’s discretion. Black should be capitalized.


Avoid unnecessary wordiness. If it can be said in one word, use one word.

Instead of…


the majority of

most or many

prior to


at the present time


at the time that


in terms of

in, of, for

the truth is


the facts are


in order to


large in size


period of time


very unique




Avoid using burden because it has a vague meaning: it can mean high prevalence, severity of symptoms, high economic costs, etc. Instead, use alternatives like extent, degree, effects, etc. Ok to refer to a “global burden” or a “country’s burden.” The word impact may also be used if referring to the global effect (note: some WHO publications require use of “burden”).

case, patient

A case is a particular instance of disease, illness, injury, or asymptomatic disease. Distinguish between a case (a situation or set of circumstances) and a patient (a human being). Cases do not show symptoms, experience side effects, recover, or die; patients do. Do not dehumanize persons into cases. (“Case-patient,” however, is an acceptable term.)

C. perfringens was isolated in a case of diarrhea. or …from a patient with diarrhea.

Erythromycin is recommended for treating patients with legionellosis.

Avoid use of case except for cases of disease. Phrases like in this case or in any case may be changed to in this instance or in any event, unless referring to a case of disease.


Use CE (“of the Common Era”) instead of AD (anno Domini, “in the year of the Lord”).

The abbreviation should be set in small caps.

comorbid, comorbidities

Use concurrent condition(s) instead. 

compare to, compare with

Use compare to for items that are very different. Use compare with for items that are similar. In scientific writing, compare with is most often used.

The sodium levels of the patients in the control group were compared with those of the patients in the study group.

Shall I compare thee to a summer’s day?


Use reported or described rather than complain (e.g., the patient reported that she had a fever).

compose, comprise

Compose: to total, form, to go together, to make up (an object); always takes the passive voice.

The district is composed of 3 counties.

Comprise: to include, to contain, to be made up of (always takes the active voice; do not say is comprised of). The whole comprises the parts; the parts do not comprise the whole.

The district comprises 3 counties.

continual, continuous

Continual means to recur at regular and frequent intervals. Continuous means to go on without pause or interruption.

The patient with emphysema coughed continually.

His labored breathing was eased by a continuous flow of oxygen through a nasal cannula.


Reduction of disease incidence, prevalence, morbidity, or mortality to a locally acceptable level as a result of deliberate efforts; continued intervention measures are required to maintain the reduction. Also see entries for elimination of disease, elimination of infection, eradication, and extinction.

dehumanizing terms

Describe a person as having a condition, not being the condition.

person with diabetes, not a diabetic

person with arthritis, not an arthritic

person with asthma, not an asthmatic

Note that patient refers to someone receiving treatment for a particular condition. In, for example, a seroprevalence study of persons with HIV infection, person with HIV is preferable to AIDS patient, unless the sample is being evaluated or receiving treatment for the clinical condition of AIDS.

Do not refer to a person as a subject. Use patient or participant.


Diseases develop in patients. Patients do not develop diseases.

developed country, industrialized country

Use industrialized, not developed.

developing country

Use developing or resource-limited, not undeveloped or Third World.


To evaluate, identify. Conditions, syndromes, diseases, and pathogens are diagnosed. Patients are not diagnosed.

die of, die from

Patients die of, not from, specific diseases or disorders.

different from, different than

Use different from, not different than.

dosage, dose

Dosage implies a regimen; dose implies a quantity. Dosage is the amount of medicine to be taken by a patient in a given period; dose is the amount taken at one time.

due to, owing to

These terms are not synonymous and can be vague. Whenever appropriate, replace with caused by or because of.

ecologic, ecological

 Follow author preference.


This abbreviation means “for example” or “such as.”

Only use the abbreviation within parentheses. Place a comma after the abbreviation.

Examples may be introduced by e.g. but should not be followed by e.g.

Correct: In evaluating an IQ score, several factors (e.g., socioeconomic level) must be considered.

Incorrect: Socioeconomic level, e.g., is a factor to be considered.

eliminate, eradicate

Disease is eradicated from the entire world, eliminated from a country or region. See separate entries for elimination of disease, elimination of infection, eradication, extinction, and control.

elimination of disease

Reduction to zero of the incidence of a specified disease in a defined geographic area as a result of deliberate efforts; continued intervention measures are required. Also see entries for elimination of infection, control, eradication, and extinction.

elimination of infection

Reduction to zero of the incidence of infection caused by a specific agent in a defined geographic area as a result of deliberate efforts; continued measures to prevent reestablishment of transmission are required. Also see entries for elimination of disease, control, eradication, and extinction.


This suffix indicates in the blood and should not be used in the plural.

Parasitemia or levels of parasitemia, not parasitemias

epidemic, endemic

A disease is endemic to an area; the area is not endemic.

endemic malaria, disease-endemic areas

Epidemic, a disease that occurs suddenly and in numbers in excess of what would be expected (because it was introduced from outside).

Endemic, belonging or native to a particular people or country, indigenous.  Use “to” with a place and “in” with a population.

Diseases endemic to the tropics

Infections endemic in European wild rodents

era designations

See BCE and CE.


Permanent reduction to zero of the worldwide incidence of infection caused by a specific agent as a result of deliberate efforts; intervention measures are no longer needed. Also see entries for elimination of disease, elimination of infection, control, and extinction.

erythrocytes, red blood cells

Use erythrocytes, when possible.


Avoid in scientific writing; it is vague.

expire, die

Patients do not expire or have fatal outcomes; they die. Medications expire.


The specific infectious agent no longer exists in nature or the laboratory. Also see entries for elimination of disease, elimination of infection, control, and eradication.

feel, believe

Use feel to express physical sensations; use believe to express personal conviction, accepting something as true.

The patient felt cold.

The author believed that the theory was sound.

fever, temperature

Fever is a rise of body temperature above normal. If a patient has a temperature of 37.8°C, he has a fever of 0.8°C. Also correct: The patient was febrile (37.8°C).

Please use the Times New Roman degree symbol; do not use a superscript lowercase o.

few, less (fewer, less; fewest, least)

Few refers to units or people that can be counted.

Less refers to quantities of mass, bulk, or volume.

genomic segments

Define as large (L), medium (M), or small (S).


Gram should be capitalized and never hyphenated when used as Gram stain; gram negative and gram positive should be lowercase and only hyphenated when used as a unit modifier.

Gram staining

gram negative

gram-positive bacteria

Greek letters

Greek letters are preferred to words in most circumstances. In some chemical names, however, the approved nonproprietary name uses the word.

tumor necrosis factor α, β-blocker, interferon-γ, betamethasone, beta carotene

Chi square should always be written as χ2. If the symbol begins a sentence, rewriting the sentence may be desirable.

hand, foot and mouth disease

Do not add a comma after "foot."

homosexual, bisexual, gay

Using these terms as adjectives is acceptable, as in “gay men,” and dependent on the author’s discretion.  However, avoid using these terms as nouns as they may too vague or perceived as perjorative.  Sometimes the phrase “men who have sex with men” or MSM is used because some of these men do not label themselves as gay, homosexual, or bisexual.

Vague: homosexuals (the term does not specify the sex)

Clear: gay men, lesbians, bisexual persons, heterosexual persons

highly pathogenci avian influenza, HPAI

Use the term “highly pathogenic avian influenza” not “high pathogenicity avian influenza.” If used >3 times, the term can be abbreviated as HPAI. Also see “low pathogenicity avian influenza.”


Use “admitted to the hospital” rather than “admitted to hospital.”

-ic, -ical

Dispense with most -al endings. For example, use epidemiologic, geographic, serologic, logistic, immunologic, toxicologic, anatomic. However, check dictionary and consider author’s preference (e.g., biological warfare, ecological, psychological).


This abbreviation means “that is” or “in other words.”

Only use the abbreviation within parentheses. Place a comma after the abbreviation. For more details, see the entry for e.g.

immunize, vaccinate

Immunize means to confer immunity; vaccinate means to administer vaccine.


This trendy word is a red flag for editors. Editors tend to avoid it because it is overused and imprecise and to reserve its use for physical collision or global effect. Whenever possible, a more specific word should be used; otherwise, effect (noun) and affect (verb) are good alternatives.

Avoid: Combination therapy with metronidazole impacted colonization rates.

Better: Combination therapy with metronidazole affected colonization rates.

Preferred: Combination therapy with metronidazole decreased colonization rates.


This word is vague and should be avoided. In most cases, it can be deleted without affecting meaning or changed to a more specific adjective.

Avoid: These data suggest important abnormalities…

Preferred: These data suggest abnormalities…

in, among

Conditions usually occur in, not among, persons.

The 25 cases of measles were in school-aged children.

infection in patients, not infection among patients

incidence, prevalence

Incidence (a rate) refers to the number of new cases per unit of population per unit of time. Prevalence refers to the number of existing cases per unit of population at a given time (point prevalence) or in a given time (period prevalence). Refer to cases per unit, not incidence or prevalence per unit.

Correct: cases per 100,000 population

Incorrect: incidence (or prevalence) per 100,000 population


This word indicates that a partial list follows. Do not use it if your list is complete.

Correct: The alphabet includes the letters a, b, and c.

Correct: The first 3 letters of the alphabet are a, b, and c.

Incorrect: The first 3 letters of the alphabet include a, b, and c.

individual, person

Person is a noun; individual is an adjective (e.g., an individual student). Avoid using individual as a noun to refer to persons (animals okay).

influenza season

Truncate second year for influenza season, when the range is ≤ 1 year, and when first 2 digits are the same.



2000–2002 and 1999–2000

Truncation may be used for other periods that do not follow a calendar year (e.g., school years, fiscal years).

injection drug user(s)

See “persons who inject drugs.”

intravenous drug user(s)

Be aware of the difference between persons who inject drugs (PWID) and intravenous drug users (IVDUs). The former includes persons who inject other forms of drugs (e.g., intramuscularly injected drugs).

insure, ensure, assure

Insure means to guarantee life or property against risk (e.g., to underwrite; to give, take, or procure insurance). Ensure means to make certain or guarantee. Assure means to make safe, to give confidence to.

in vitro

Do not hyphenate foreign phrases that are printed without a hyphen in other circumstances (e.g., in vitro translation, in situ protein synthesis, in vitro–stimulated growth, in situ–synthesized proteins).

large T-antigen

See “t-antigen.”

last, past

Although last is not wrong, most recent or past is often more precise. Last can mean final.

Patients were included if they were symptomatic for the last 10 days. (These are only their last 10 days if they died; past is better.)

Patients reported condom use at their last sexual encounter. (May not be their last; most recent is better.)

leukocytes, white blood cells

Use leukocytes, when possible.

low pathogencity avian influenza, LPAI

Do not use “low pathogenic avian influenza.” If used >3 times, the term can be abbreviated as LPAI. Also see “highly pathogenic avian influenza.”

male, female

As nouns, these terms can be considered dehumanizing and are best reserved for laboratory animals. They can be used as adjectives (male adolescents, female participants), but as nouns referring to humans, they should be replaced by men and women or boys and girls.


Manifest is a transitive verb and, as such, requires a direct object.

Incorrect: Disease X manifests as coughing, sneezing, etc.

Correct (best alternative): The signs of disease X are coughing, sneezing, etc.

Also correct: Clinical manifestations of disease X are coughing, sneezing, etc.


Might is more specific.


MIC and MBC, minimal inhibitory concentration and minimal bactericidal concentration, respectively, are properties of drugs; they are not properties of bacteria. The terms should not be spelled out or explained, except when MIC is used in MIC50 (meaning MIC for 50% of the strains).

Correct: The MIC of rifampin for Mycobacterium tuberculosis is 16 µg/mL.

Correct: Mycobacterium tuberculosis requires an MIC of 16 µg/mL.

Incorrect: Mycobacterium tuberculosis has an MIC of 16 µg /mL.

Incorrect: The MIC of Mycobacterium tuberculosis is 16 µg /mL.

Correct: MIC of a drug

Incorrect: MIC to a drug

The word “value” should not be used with MIC or MBC.

Incorrect: MBC values.

Correct: MBCs

molecular weight

The relative mass of a substance. It is a pure number and has no units.

Incorrect: The molecular weight of the protein is 30,000 Da.

Correct: The molecular weight of the protein is 30,000.

Correct: The molecular mass of the protein is 30,000 Da.

morbidity, morbidity rate

Morbidity refers to the condition of being diseased, the rate of illness or disease. Do not use morbidity if illness or disease would work; use morbidity only to refer to the rate of illness in a specified population during a specified time (morbidity rate).


Morphology refers to the features that constitute the form and structure of an organism and its parts. Morphology is not a synonym for shape, and such statements as “The cell showed a flat morphology” are wrong.  In this example, the statement should be “The cell was flat.”

mortality, mortality rate

Mortality refers to the number of deaths from a particular condition. Death is preferred over mortality. Mortality rate is the number of deaths in a particular population divided by the size of that population at the same time.

multilocus variable-number tandem-repeat analysis

Use as shown.

negative, normal

Examinations and most laboratory tests are neither negative nor normal in and of themselves; interpretations of the test results, however, may be negative or within normal limits.

Observations, results, or findings from examinations and tests are within normal limits or abnormal.

Incorrect: Urinalysis was normal.

Correct: Urinalysis results were within normal limits.

Cultures, tests for microorganisms, tests for specific reactions, and reactions to tests may be negative or positive (reactive, for some).

Electroencephalograms, electrocardiograms, isotope scans, and radiographs are pictures and are, therefore, not negative or positive.

normal values

Incorrect: normal values or normal ranges

Correct:  reference values or reference ranges


Use children, not offspring, for humans.


This suffix means a branch of knowledge, science, or study of something. Terms ending in -ology (e.g., etiology, pathology, serology) should not be used to describe particular items. All “ology” words refer to the study of something.  For example, the methodology of a research study would be a study of the methods used within the study, while the methods would include the study design and other information about how the study was conducted by researchers.

Incorrect: The pathology was located in the upper part of the gastrointestinal tract.

Correct: The pathologic lesion was located in the upper part of the gastrointestinal tract.

Incorrect: The histology was small-cell carcinoma of the lung.

Correct: The histologic diagnosis was small-cell carcinoma of the lung.

Incorrect: The patient’s serology showed…

Correct: The patient’s serologic test results showed…

Incorrect: We used the following methodology.

Correct: We used the following methods.


Parameter has a specific statistical meaning and should not be used to mean measurement, value, or number. Ordinarily, except when a descriptive quantity for a statistical population is meant, parameter should be changed to measurement, value, quantity, variable, number, or a comparable term.


An ill person who is receiving or has received medical care. Do not use the term normal patient.

PCR, real-time reverse transcription

Always abbreviate PCR, even on first usage, and always write out real-time on every usage. Reverse transcription is preferred rather than reverse transcriptase, and is abbreviated RT after first usage if used 3 or more times. Real-time can be abbreviated as r when used with RT-PCR (rRT-PCR) if used 3 or more times.

person, persons, people

Person is preferred over individual as a noun. The plural of person is persons, not people. The latter term refers to a group of persons who share particular characteristics (e.g., the American people).

persons who inject drugs

Use “persons who inject drugs” (PWID) instead of “injection drug users.” This usage is in accordance with usage by the World Health Organization (

Be aware of the difference between PWID and IVDUs (intravenous drug users). The former includes persons who inject other forms of drugs (e.g., intramuscularly injected drugs).


preferred over thrombocyte

population, sample

Population refers to the set of entities from which statistical inferences are to be drawn. Sample is that portion of the population that is under study.

present, present with

As a synonym for seeking treatment, the word present is jargon and should be avoided.

Incorrect: The patient presented with…

Correct: The patient sought treatment for…

Correct: The patient had…

preventative, preventive

Preventative is becoming obsolete; preventive is preferred.


A picture produced on a sensitive surface by a form of radiation other than visible light; an x-ray or gamma ray photograph (includes CT but not MRI images).


A radiograph.


The process of making a radiograph or sonogram.

rate, ratio

Rate is the incidence of a disease (or number of deaths) in a specified population in a specific time period. If no time period is specified, ratio is preferred.

The overall case-fatality ratio for SARS is ≈12%

The rate of West Nile virus infection in Canada is ≈300 per 100,000 population per year.

react, test

A substance is tested for a reaction with another substance; it is not reacted with another substance.


Symptoms are resolved; patients do not resolve their symptoms.

risk of, for, from

What is my risk of getting AIDS?

Men who have sex with other men are at highest risk for AIDS.

The most serious risk from AIDS is death.

To avoid categorization by group, do not use high-risk as an adjective. Similarly, replace high-risk groups with groups at high risk.

Incorrect: high-risk youth

Correct: youth at high risk


A euphemism for killing laboratory animals after an experiment. Preferred terms are humanely kill or euthanize.


Spell out severe acute respiratory syndrome at first use.

It is permissible to use SARS in the title of a dispatch or letter provided it is defined in the abstract of the dispatch or the first paragraph of the letter.

serum, sera

Serum and the names of other body fluids should not be singular if they mean samples collected from different patients. Change serum of patients to serum samples or serum specimens. Be sure to use the word samples or specimens if a specific number is given: 14 serum samples, not 14 sera.

severe acute respiratory syndrome

Spell out at first use.

It is permissible to use SARS in the title of a dispatch or letter provided it is defined in the abstract of the dispatch or the first paragraph of the letter.

sex partner

Use the term sex partner, not sexual partner; however, the term sexual behavior is correct.

since, because

Using since when you mean because can create ambiguity (causal vs. temporal).

Vague: Since they began treatment, the patients were more active.

More clear (meaning #1): Because they began treatment, the patients were more active.

More clear (meaning #2): After they began treatment, the patients were more active.


Significant has a specific statistical meaning. If that is not the meaning intended, substitute a synonym, e.g., marked, noteworthy, substantial. When using in the statistical sense, the modifier statistically is redundant.

Incorrect: We included all statistically significant variables in the multivariate model.

Correct: We included all significant variables in the multivariate model.

small t-antigen

See “t-antigen.”

Southeast Asia

Do not use other variations of this term.

stool and stool sample

The terms feces/fecal sample are preferred. However, in some cases, the use of the term stool is ok (e.g., to discern between a discussion of fecal swab specimens and fecal [i.e., stool] samples in the same paper).

Student t-test

Capitalize Student, italicize t, and use a hyphen.


Do not refer to human participants as subjects. Substitute participant, patient, or person.


Be sure to clarify whether survival refers to times or rates, i.e, distinguish between patients living longer or more patients not dying.


For the term “large T-antigen,” use a capital letter “T”; for the term “small t-antigen,” use a lowercase letter “t.”


This term is dehumanizing and often misused. Targeting people is like painting a bulls-eye on them. If you must target something, be sure you do not confuse it with aim.

Dehumanizing: Our program targets low-income women.

Better: Our program serves low-income women.

Better: Our program addresses the needs of low-income women.

Incorrect: We targeted the program to low-income women.

Better: We focused the program on low-income women.

Incorrect: We targeted the intervention to rural areas.

Better: The intervention targeted rural areas.

For testing, “selective for” is more specific than “targeting.”

test positive

Samples, but not patients, can test positive.


Use platelets.

time designations

From March to August (excludes August)

From March through August (includes March and August)

Between March and August (excludes March and August)

1960s, not 1960's

once a day, not daily or qd

twice a day, not twice daily or bid

1986 to 1987 (1-year period). Between 1986 and 1988 is also a 1-year period [1987]).

1986 through 1987 (2-year period)

1986–1987 (2-year period)

AM, PM (small caps)

BC, AD (small caps)

3:00 PM, not 15:00


Use the word "times" (not the mathematical symbol x) in the following context:  the score for the control group was 64 times higher than that for the case-patient group.


Use only as a noun, not a verb, and use American spelling.

Incorrect: were titered

Correct: titers of… were determined

Titer reflects dilution, not optical density. For optical density, state the optical level that determines positivity.

Use a colon to express a ratio or dilution. Titers are expressed as the reciprocal of the dilution.

(length:width, 2:1)

The end IgG titer was 256 after a serial 1:2 dilution.


The use of the word tracking is considered jargon when used in place of proper English.

Incorrect: tracking people

Correct: analyzing trends among persons


Avoid anti-[disease] treatment.

Preferred: TB treatment

Avoid: anti-TB treatment


The word using probably causes more dangling participles than any other word.

Incorrect: Using inhalation anesthesia, the dogs were splenectomized.

Correct: Using inhalation anesthesia, we splenectomized the dogs.

Using requires the word by when the actor is not specified.

By needed: Age was determined by using body mass and/or reproductive characters.

By not needed: We calculated age-specific hospitalization incidence rates and fitted linear models, using the χ2 test.

US citizens

Preferred rather than the term Americans.

vaccinate for/vaccinate against

Use of either term is acceptable depending on context.

varying, various

Varying means that which is changing (adjective) or causing to change (verb).

Various means of different kinds or aspects.


Use versus in running text and titles, vs. in parenthetical expressions and tables, and v. in legal citations.  Do not use vs. without periods.

Kirby-Bauer disk diffusion versus serial dilution

(3.9 for case-patients vs. 7.2 for controls)

Roe v. Wade

while, although

Although is more precise when you mean in spite of the fact that. While also has a temporal meaning of during the time that.

Vague: While a vaccine is not yet available, many candidate vaccines are being tested. (Either meaning could apply.)

More precise: Although a vaccine is not yet available, many candidate vaccines are being tested. (Has only 1 meaning.)

White, Caucasian

White refers to a person whose origins are in any of the original peoples of Europe, the Middle East, or North Africa. Due to the international audience of the journal, the use of the term White is preferred unless referring to persons from the Caucasus region. White should be capitalized.

whole-genome and whole genome

Hyphenate this term when it is used as an adjective describing another word (e.g., whole-genome sequencing).


Italicize z and use a hyphen.


Additional Information:

Geographic Designations
Scientific Nomenclature
Units of Measurement

Page created: February 04, 2010
Page updated: April 22, 2021
Page reviewed: April 22, 2021
The conclusions, findings, and opinions expressed by authors contributing to this journal do not necessarily reflect the official position of the U.S. Department of Health and Human Services, the Public Health Service, the Centers for Disease Control and Prevention, or the authors' affiliated institutions. Use of trade names is for identification only and does not imply endorsement by any of the groups named above.
edit_01 ScholarOne Submission Portal
Issue Select

Coronavirus Spotlight

Spotlight Topics


Get Email Updates

To receive email updates about this page, enter your email address: