What changes when a medical text moves between languages
A medical translation may change length, register, sentence structure and terminology while preserving meaning. Differences between language variants, healthcare systems and professional roles can require contextual equivalents or explanations rather than direct word substitution.
Length and sentence structure
A practical estimate for English-to-Russian text expansion is 9%–25%, because one English word may require two, three or more Russian words. Average word length is five letters in English and six or seven in Russian; English has thousands of three-letter words, while Russian has about 300. Russian texts tend to be longer, less personalised and more passive, with additional explanations and more variable word order than concise English with its fixed order. Moving between these patterns can be particularly demanding when handling several documents in both languages.
French tends to use more words and longer sentences than English: a ten-page French publication may become eight pages in English, affecting format and design and warranting discussion with the client. Long French sentences often need splitting for clarity and readability in English, with adaptation to target-language grammar and syntax.
German frequently uses subordinate clauses, sometimes several, with verbs usually moving to the end of a clause or sentence. Its more flexible but complex sentence structure can express precise, extensive information while making the main action hard to follow, especially for non-native readers. Writers need careful logical flow and coherence, and English translations often require restructuring to preserve meaning.
Register, audience and purpose
In European Portuguese, the English word “headache” becomes cefaleia in a summary of product characteristics and dor de cabeça in a patient information leaflet. Translators must choose formal or informal register for the audience, keeping patient instructions clear and clinical reports precise.
German distinguishes formal and informal address, unlike English. Formal address is usual professionally, but pharmaceutical companies increasingly used informal patient address in 2024 to create a personal connection. Informality can engage patients directly and appear modern, while formality can seem stiff; however, some patients, especially older people, may feel disrespected by informal address. Tone therefore needs to suit the document, audience and company preference.
Russian regulatory documents, scientific articles and conversation use markedly different styles, more so than in English, so protocols, articles and even short clinical-trial advertisements need purpose-specific terminology and phrasing. By 2024, one Russian-language writer had observed regulatory documents becoming simpler as structure and content were harmonised with international English-language guidance.
German compound nouns combine several nouns into one descriptive word and can become long. Nahrungsmittelunverträglichkeit means food intolerance, combining Nahrung (food), Mittel (product or stuff) and Unverträglichkeit (intolerance). Such compounds are standard in scientific and administrative documents but can challenge concise public brochures and advertorials.
Variants and unsettled terminology
Spanish is spoken in 21 countries on three continents, with differences in words, phonetics and syntax. Contact with English-speaking neighbours encourages false friends: constipado means common cold, not constipation (estreñimiento), and injuria means offence, not injury (lesión). English accounted for 94% of Web of Science articles in 2022, compared with 1.3% for Spanish, so Spanish scientific writing almost inevitably involves translation from English. Individual scientists or linguists often make divergent or questionable choices, leaving medical Spanish less standardised than medical English.
Spanish medical synonyms arise through several mechanisms:
| Mechanism | Examples |
|---|---|
| Geographical variants | útero / matriz for uterus |
| Semantic calques | fármaco / droga for drug |
| Syntactic calques | por VIH, VIH-asociado or HIV-asociado for HIV-associated |
| Crude or adapted lexical loans | derivación, bypass or baipás for bypass |
| Anglicised spellings | glucemia / glicemia for glycaemia |
| Alternative etymologies | nefropatía / enfermedad renal for kidney disease |
| Misinterpreted noun phrases | valor de p / valor p for p value |
Acronyms multiply through lexical and syntactic alternatives: small interfering RNA, or siRNA, can become ARNpi, ARNip, pARNi, siRNA, siARN or ARNsi, among other variants. Three writers moving from molecular biology, biochemistry and physics research into language work found specialised Spanish terminology unexpectedly difficult after years working with specialised English.
Portuguese has significantly different national variants, making audience locale crucial to alignment with local practices. Infusion as a method of administration is perfusão in European Portuguese, where infusão means a tea or herbal drink, while infusão is correct in Brazilian Portuguese. “Randomised” is aleatorizado in European Portuguese and randomizado in Brazilian Portuguese.
Most online medical Portuguese is Brazilian, complicating fact-checking for other variants. Even authoritative sources may be inconsistent because of excessive Anglicisms, borrowing from other variants, evolving knowledge, differences between academic and clinical usage and insufficient expert writing or translation input; terminology therefore requires judgement by context and audience.
Russian and English share Indo-European roots, helping with grammar and concepts, while Latin-derived medical terminology also aids translation. Some clinical-trial and registration terms still lacked universal Russian equivalents in 2024: estimand was used as эстиманд, and GCP, GLP and GMP were used unchanged. GCP means Good Clinical Practice, GLP Good Laboratory Practice and GMP Good Manufacturing Practice.
Concepts, abbreviations and professional roles
Healthcare systems can contain concepts absent from the target language. French carte vitale, literally “vital card”, may need a translator's note explaining the state-issued electronic health-insurance card, depending on the audience.
Publications normally expand abbreviations at first use, but medical reports rarely do, so translators may need to research them. French VIH reverses to English HIV; NFS (numération formule sanguine) means complete blood count; and EVA denotes the pain-intensity visual analogue scale, VAS in English.
Professional titles also require contextual equivalents: English-speaking countries' nurse practitioners often perform responsibilities assigned to doctors in Portuguese-speaking countries, with substantial variation in autonomy and scope.