ISSN: 1080-6059
Set nonrestrictive clauses (extra information) off with commas and introduce them with "which."
The samples, which James analyzed, had been stored for 2 weeks.
(Only 1 set of samples is being discussed; therefore, the clause "which James analyzed" is not necessary for defining the samples.)
Do not place commas around restrictive clauses (necessary information) and introduce them with "that."
The samples that James analyzed had been stored for 2 weeks.
(More than 1 set of samples is being discussed. The clause "that James analyzed" defines the noun "samples," telling which samples were analyzed.)
Use a singular verb with a singular subject and a plural verb with a plural subject, even if a plural phrase follows the subject.
Our analysis of all patients with E. coli infections shows…
Collective nouns (e.g., number, total, staff, faculty) take a singular verb when the noun is regarded as a group and a plural verb when individual members of the group are emphasized. A good rule of thumb is to use a singular verb when the article is "the" and a plural verb with "a".
The number of patients was unclear.
A number of patients were quarantined. [patients were quarantined individually]
The number (total, group) reported is 25.
A number (total, group) of persons are…
Seventy-eight percent is the largest percentage reported.
The Centers for Disease Control and Prevention is...
In a noncount noun in a prepositional phrase with "none," the verb plurality is determined by the object of the preposition.
None of the blood was...
None of the patients are participating.
dialyze blood, not animals or humans
transfuse blood, not animals or humans
A quantity indicated by a unit of measure is singular, even when the units are spelled out (ASM).
Twelve milliliters was injected.
...10 mg was added
...5 mL was injected
...220 cpm of radioactivity was detected
Exceptions:
Nonabsolute or informal units
...10 drops were added
Do not allow a mathematical symbol to stand for the main verb in a clause (ASM).
Incorrect: When p <0.005...
Correct: When p was <0.005...
Medical jargon often uses nouns as verbs. Avoid.
Incorrect: was electrophoresed
Correct: underwent electrophoresisIncorrect: The patient was biopsied.
Correct:A biopsy was performed.
See also Apostrophes.
Year indications are not possessive.
1960s, not 1960's
Organization names vary:
American Medical Writers Association
Department of Veterans Affairs
Please contact the EID Editors at eideditor@cdc.gov
The opinions expressed by authors contributing to this journal do not necessarily reflect the opinions 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.
This page posted January 29, 2009
This page last reviewed August 12, 2009
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