Keeping apart words that are easily confused
Many errors in medical text put a word that looks, sounds or means nearly the same in place of the right one: one of a pair of homophones, a noun used for its adjective, a fixed expression mixed with another, or a looser word where the distinction matters to the reader or to someone who acts on the word. Keeping such words apart means knowing the pairs to check and when a distinction is worth keeping even where nobody would be misled.
Words that look or sound alike
Most writers occasionally get stuck choosing between two words, especially homophones or homonyms, which one writer defines respectively as words that sound alike but have different meanings and words that sound alike but are spelled differently. Some pairs are both, and some confusing pairs are related words with slight differences in meaning. Authorities differ somewhat on the definitions of homophone, homonym and oronym, but the resulting problems remain. Such pairs are many and occur rather frequently. They are no crisis for good writers, but they make them pause briefly and make a conscious effort to choose the right word, and when a writer is really stymied, a brief visit to a dictionary will solve the problem.
Pairs that often occur in medical writing include these:
- Chord and cord. A chord is, in general, a musical sound, and a cord is a long, rounded, flexible body or organ. Vocal cord sometimes confuses writers because both words are associated with sound, whereas spinal cord fits the description of a cord and rarely gives problems.
- Breech and breach. Breech has definitions all relating to the hind end of the body and is mostly used in obstetrics, as in breech presentation. A breach is a temporary break in the continuity of something, or a broken or torn condition, as in breach of contract.
- Callus and callous. A hardened or thickened area on skin or bone is a callus, a noun, whereas callous is an adjective meaning, in most common usage, indifferent to something personal and, in medicine, hardened and thickened. Thinking about which part of speech the sentence needs will sometimes show which one to use.
- Principal and principle. The noun principle is a fundamental law or rule, whereas principal can be a noun or an adjective, as in The principal met all the teachers or The principal argument was lost on the crowd.
- Regime and regimen. A ruling party, a political tenure or a mode of management is a regime, whereas a regimen is a systematic plan, as in The injured man was placed on a regimen of neurological care.
- Criteria and criterion. The first is plural and the second singular. The confusion mainly arises when a writer discusses criteria and then mentions one item, which makes it singular, a criterion.
- Specious and spacious. Specious usually means showy or deceptive, or looking false, whereas spacious simply means roomy.
- Autopsy and biopsy. An autopsy is the postmortem examination of a body, and a biopsy the removal of some tissue from a living body for examination and study.
Many terms and expressions are prone to erroneous use, and native speakers of English may struggle with them as much as nonnative speakers do. The pairs below are some of the troublesome ones, and the list is by no means exhaustive.
| Distinction | Meaning to check |
|---|---|
| Accident / incident / injury | In medical reporting, accident only for an unpredicted and unforeseen event / incident where the event has a cause / injury may be synonymous with incident but may also indicate the type of organ lesion |
| Compliment / complement | Offering praise or flattery / something that completes or goes well with something else |
| Irregardless / regardless | Irregardless is a no-word / the correct word is regardless |
| Less / fewer | Things that cannot be counted, as in We added less water / anything that can be counted, as in There were fewer people around or The probes contained fewer cells |
| Loose / lose | Something, such as a knot, may be loose / something lost cannot be found |
| Then / than | An adverb of time, as in Then, we applied an ANCOVA / introduces a comparison, as in Formulation A was considerably more stable than Formulation B |
| There / their | Completely different meanings but frequently confused: There are a number of mistakes in this paper / Their papers contained a number of mistakes |
| Assure / ensure / insure | To remove doubt or guarantee something, as in I assure you of the correctness of my data / to make something certain, as in We ensured the correctness of the data / to provide insurance, as in The laboratory is well insured |
| Can / may | Can for ability or power to do something / may for permission to do it, a traditional distinction that, in one usage guide's words, the writer attentive to the proprieties preserves, whatever the interchangeability of the two in spoken or informal English |
| Lie / lay | Intransitive, indicating a position, as in The manuscript lies on the table / transitive, indicating an action and requiring an object, as in The authors laid it there |
Mitigate is not militate against: the former has a favourable resonance, as in lessening something noxious, whereas the latter suggests an undermining or countervailing force.
An electronic spellchecker does not catch a misspelling that is itself a valid word, such as complaint and compliant, creatine and creatinine, dairy and diary, infraction and infarction, relive and relieve, or trail and trial written one for the other.
A poem run through a spellchecker shows the same problem with words that sound alike: Eye have run this poem threw it / I am shore your pleased to no / Its letter perfect in it's weigh / My chequer tolled me sew.
A noun and its adjective
Seeking out new words to brighten up a text is commendable, but doing so without first checking a dictionary is perilous. Making an adjective out of a noun can change the meaning dramatically: in The basis for the measurement of functionally active A1PI was laid by the synthetic work of Bieth et al. who described the synthesis of the convenient and water-soluble chromogenic substrate, the adjective synthetic turns the work on synthesis into a fake.
Mistaking an adjective for a noun, or a noun for an adjective, is in one medical editor's experience an extremely common error in medical writing and particularly in medical journalism, as with mucus and mucous and with phosphorus and phosphorous. Mucus is a noun and mucous an adjective, made one by the suffix -ous, which is glossed both as pertaining to and as full of, having the quality of, or possessing. Mucus contains sloughed-off cells, leukocytes and inorganic salts, whereas mucous membranes are thin sheets of tissue that line and protect the digestive tube, the genitourinary tract, the respiratory passages and innumerable other anatomic parts. Phosphorus is an element of the nitrogen family and a noun, whereas phosphorous is an adjective that means phosphorescent and also describes a compound in which phosphorus has a lower valence than in phosphoric compounds. When the element stands alone, and in lists of blood chemistry values, it should always be phosphorus.
Mixed expressions
A fixed expression can be mixed up with another. The title Lessons raised by the major 2010 dengue epidemics in the French West Indies leaves a reader wondering what questions were learned. He wouldn't trust them with a ten-foot pole mixes I wouldn't trust them as far as I could throw them with I wouldn't touch them with a ten-foot pole. It remains entirely possible that quantitative differences exist between mice and humans in terms of target organ affection muddles the expression object or target of affection with the verb affect.
Affect and effect, efficacy and effectiveness
Affect and effect can each be a noun or a verb, and that is what causes the difficulty. Affect as a noun is stressed on the first syllable, has to do with emotion or a range of emotions, as in flat affect, and is rarely used except in psychology and psychiatry. It means the outward expression of emotion, and a person who no longer expresses emotions normally shows flattening of the affect. Affect as a verb, accented on the second syllable, means to have an influence or effect on something or to act on it, and effect as a verb means to execute, accomplish or achieve. Affect as a verb seldom causes trouble except when the writer is not sure of the spelling. The flow rate affected the output uses affect correctly. Effect as a verb is rarely used, and The treatment effected superior survival rates is correct but better written The treatment improved the survival rates. Too low a blood glucose level can affect the functioning of the brain, causing seizures, coma or death and To effect a change in attitude, the therapist may try effecting a change also in the life situation use both verbs correctly. Mnemonics may help: to affect is to alter or act on, to effect is to execute, and to be effective is to be efficient; for the nouns, flat affect and end effect. A sentence telling patients not to take a medication if they are using or have used drugs expected to effect norepinephrine should use affect.
Pharmacologists, researchers and medical writers specialising in regulatory work distinguish efficacy from effectiveness. Stedman's Medical Dictionary (27th edition) defines efficacy as a beneficial result under ideal conditions, and effectiveness as the accuracy or success of a diagnostic or therapeutic technique in an average environment. Dorland's Illustrated Medical Dictionary (29th edition) defines efficacy, in pharmacology, as the ability of a drug to produce the desired therapeutic effect, independent of potency, which expresses the amount of the drug necessary to achieve that effect, and effectiveness as the ability of an intervention to produce the desired beneficial effect in actual use. The FDA, for example, differentiates the two in investigational new drug applications (INDs) and other documents.
Confusing effectiveness with efficacy, and writing verbal where the correct word is spoken, were pet peeves of one medical editor.
Positive and negative
Positive and negative have different meanings in different contexts, and a writer who uses them carelessly might say the opposite of what they mean. Posit comes from the Latin positus, the past participle of ponere, to put, and negate from negatus, the past participle of negare, to deny. Thus positive can imply affirmation, addition, inclusion or presence, whereas negative can imply denial, subtraction, exclusion or absence. In laboratory medicine, positive is generally used to mean presence and negative absence, so a positive test result suggests that something is present and a negative one that it is absent. These results may be good or bad news depending on which outcome is wanted: a positive result of a pregnancy test is good news to someone who wants to be pregnant and bad news to someone who does not. In a specimen that has undergone Gram staining, the purple bacteria are gram-positive and the pink bacteria gram-negative, and a finding of gram-negative organisms in a sample of spinal fluid is not a negative result but a positive result that confirms the presence of bacterial meningitis. Psychiatry also uses positive to mean presence and negative to mean absence. The positive symptoms of schizophrenia, such as hallucinations, delusions, confused thought and speech, and movement disorders, are symptoms that have started happening, whereas the negative symptoms, such as flattening of the affect, withdrawal from social interactions and difficulty finishing or even starting ordinary activities of daily living, represent things that have stopped happening.
In mathematics, a positive number is a real number greater than zero and a negative number one less than zero, and positive can also imply increase or progression, as in a positive cash flow, which means the amount of money is increasing. In the 18th century Benjamin Franklin used positive for items he thought had an excess of an invisible electrical fluid and negative for items he thought had a deficit of it. For reasons lost to history, he decided that glass rubbed with silk would be positively charged and amber rubbed with fur negatively charged, so that an electrical current would represent a flow of positive charge. An electrical current in fact results from the flow of electrons, which have a negative charge, so in physics the direction of the current is the opposite of the direction in which the electrons move. In photography, a positive image has shades and tones of colour similar to its subject, and a negative image the opposite. In molecular biology, the words have particular meanings with regard to the information encoded in DNA or RNA.
In many contexts positive connotes growth and progress, and so it is often used to mean good or desirable, whereas negative tends to connote loss and retreat and has often been used to mean bad or undesirable. Yet some kinds of growth are undesirable, and some decreases are desirable. For that reason, careful writers should observe these rules:
- Avoid using positive to mean good and negative to mean bad, especially in contexts where positive and negative have other meanings.
- When describing the results of a test that yields a positive or negative result, explain where needed which result is desirable and why.
- When describing the result of a test that produces a numerical value, indicate where needed whether a high score is a good or bad thing.
The precise word
In medical writing there is no danger in being too precise, only in being imprecise. A writer's tools are words, and a lack of precision in using them makes writing unclear and ineffectual. The medical literature clearly supports the need for therapies like this one misuses like: it says there is a need for therapies like this one but not for this particular therapy, and the correct wording is such as this one. In Inhaling secondhand smoke during infancy increases respiratory infections, a respiratory infection is a finite thing that cannot be increased or decreased; what could be increased or decreased is the infection's incidence, its severity or its duration.
A patient receives a heart transplant, the organ, but undergoes heart transplantation, the procedure. In one medical editor's view, through usage it is also correct to say that a patient undergoes a heart transplant. One criterion is whether a usage is ambiguous or could be misinterpreted; here there is no possibility of misunderstanding, and Webster's Third defines transplant as both noun and verb. It would be awkward and un-English to write that the patient received a heart transplantation, so the two words are not necessarily interchangeable. In well-edited medical literature the procedure itself is almost invariably described as transplantation: it is always bone marrow transplantation for the procedure, not bone marrow transplant. The alternative is not inaccurate, just not very precise. Usage is what is used, and good usage is as precise as possible within reason.
A sentence that places the kidneys on either side of the vertebral column is inaccurate, because the kidneys are on each side of it, not either side.
In one editor's view, a Methods subhead such as Generation of Mutant Mice via Gene Trapping has no reason to use via when the sentence beneath it, The mouse genes were mutated by gene trapping, says it all with by, and by or by means of is the better choice, by means of being the more medically precise and only two words longer. Via originally meant by way of, in transportation, and has come to mean, in common usage, by means of or by way of. Writers including E. B. White and John Updike have used it to mean through, by or any other preposition. It is Latin, but has been integrated into English for so long that it is no longer written in italics.
A speaker stands on a podium but behind a lectern, and the lectern does not have to be on the podium at all; it could be below it. Where stepped away from the podium and stood close to the participants is corrected to lectern, both versions can be right only if the speaker stepped away from the lectern and down off the podium or dais. Just stepping away from the lectern does not carry the same meaning, and it is leaving the podium that brings the speaker closer to the participants. Preserving the difference matters, especially to the technicians and electricians who set up the podium and the lectern. One could conceivably knock over a lectern but hardly a podium, and no one but an acrobat would jump off a lectern. For people who know Latin there is no possibility of confusion. Lectern comes from lectus, the past participle of legere, to read, and a lector is one who presides at a lectern, a reading desk with a lamp; podium, spelled the same in English and Latin, is a raised platform on which the feet are placed, from the root pes, combining form pod-, the word for foot, which also gives bipedal, podiatry, pedestrian, pedestal, pedicure and pedigree.
The parts compose the whole, and the whole comprises the parts: comprise means to include or be made up of, as in A comprises X, Y and Z, whereas compose, its opposite, means to form by putting together or to constitute, as in X, Y and Z compose A. To comprise is to enclose, include or embrace, and although one may be embraced, one cannot be comprised. Comprise is never used correctly in the passive voice, as in The National Institutes of Health complex comprises, not is comprised of, 13 institutes and several other divisions. Most purists and many grammarians think is comprised of always incorrect, although many writers of good repute use it. Compose can be used in both the active and the passive voice, as in Fifty states compose the United States and A culture is composed of diverse elements, and most people seem more comfortable with the passive in both speech and writing.
Five words commonly misused in medical writing
In one editor's experience, the five most commonly misused words in medical writing are utilize, increase, level, while and comprise.
- Utilize. Use generally means to put something into action or service, whereas utilize means to make use of and can suggest the discovery of a new, profitable or practical use for something, such as a kitchen spatula to remove ice from a windshield, a Petri dish to store paperclips, or a belt as a tourniquet. Default to use, and write utilize only when it is the more accurate choice, or better, skip utilize altogether, since use can always replace it.
- Increase. Increase means to make or become progressively greater in size, amount, number or intensity, and so implies a change over time or a cause-effect relationship, as in The prevalence of diabetes increased from 0.93% in 1958 to 7.4% in 2015 or Epinephrine increases heart rate and cardiac output. Using it to describe differences between groups of data is a misuse, most often seen as increase paired with versus, than, compared to or compared with, and higher or greater is the accurate word, as in Urine albumin was higher in patients with kidney disease than in healthy patients.
- Level. Amount means the total number or quantity, concentration the amount of a component in a given area or volume, and content the amount of a specified material, but level has several meanings, including a concentration of something, a position in a scale, a measurement or index of altitude, the magnitude of a quantity related to another value, even or unvarying height, and a device that helps establish a horizontal line or plane. Default to amount, concentration and content, and use level only when no other word will do.
- While. Although means in spite of something or even though, and whereas means on the contrary or in view of, but while can mean during a certain time, as long as, on the other hand, and at the same time as something, so it can sometimes stand for although or whereas but not always. Use while only when referring to time, and otherwise a more precise word such as although or whereas, or a more readable one such as and or but.
- Comprise. Writers misuse comprise by following it with of, likely confusing it with compose, which takes a meaning similar to comprise only when sandwiched between a weak to be verb and of, as in was composed of. Comprise and consists have similar meanings, but only consists is followed by of. Use comprise without of, as in The team comprises a physician, nurse practitioner, and resident, or use consists, as in The solution consists of 4 chemicals, and prefer either to the sandwiched form of compose, to reduce the word count and help readability.
Language constantly evolves, so the meanings of these words and how they are used may change, and the key is to stay updated on these changes so as to use the most explicit, accurate and precise words.