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Back translation

Also known as reverse translation, back translation is a potentially crucial step in the translation quality assurance process. With certain content, back translation can even be a legal or regulatory requirement.

What is back translation?

Forward translation is the practice of translating text into another (target) language. Back translation is the process of re-translating text from the target language back to its original language. One professional will undertake the translation of the source text into the target text. Another translator will handle the back translation, usually someone who has no knowledge of the original content or its context. The back translator will translate the content as literally as possible. Any errors and ambiguities in the translated content can then be identified as can any words or phrases that do not reflect the essence of the original copy. Back translations help both translation professionals and their clients to evaluate the equivalence of meaning between the source and target texts.

Are back translation methods useful?

Most content will be localised to some extent when translated. Puns, idioms, slogans and even product names may possess implied meanings that simply don’t work in the target language and/or culture. These aspects of the text must be altered or substituted to resonate with a new audience. But the processes of localisation and domestication necessitate creative input from the translator. Translation becomes subjective as the professional who is undertaking the work will choose what they believe to be the most appropriate words to use. Back translation will enable the owner of the original copy to review the choices made and how they could reflect on the brand.

The process may involve double or multiple translations. The owner of the source text could be presented with several alternative translations and their back translations. They can then assess which choice of words best represents the essence and nuances of the original.

back translation

There’s an added complication with translating slogans and taglines as they will often need to be of a certain length to be accommodated on labels or in social media posts. Translators may be forced to exercise even more creativity in producing suitable words in the target language and so there’s greater potential for the target text to diverge in meaning from the source. Back translation will help to ensure that using fewer words does not result in the sense of the source content being lost.

All languages are nuanced and so it is often impossible to produce a precise translation of content in the target language, or at least one that does not require the use of additional words. A good example of this issue would be the iconic Audi slogan “Vorsprung Durch Technik”. This is usually translated into English as “Advancement Through Technology”. However, there is no exact equivalent of the word vorsprung in English. It means something like to leap forward” or “to leap ahead”. Thus, the Audi slogan could be translated as “leaping ahead through technology” but that doesn’t sound as punchy as the original. A translator may have settled upon “progress through technology” instead, but “progress” doesn’t project the idea of leaping ahead. It sounds far more measured and so diverges from the essence of the original.

Back translation can help to identify obvious differences between the source and target text. Take the French verb “perdre”. This would normally be translated into English as “to lose” but can also mean “to destroy”. It would be unfortunate if a translator produced the output “the man destroyed his vehicle” when they should have come up with “the man has lost his vehicle”. The back translation process can also reveal more subtle divergences between inputs and outputs that could prove to be crucial.

When is back translation vital?

It is often beneficial to use back translation for the quality assurance of marketing material but perhaps not always vital. But with certain types of content, back translation is essential or even a regulatory requirement. For instance, it is crucial that instructions for the use of medical equipment and medical treatments are translated accurately. Mistakes could literally be fatal. With clinical trials, most review boards and ethics committees will demand back translations and certificates of accuracy.

back translation

Back translations are essential for the following source materials:

  1. Legal documents including contracts, case files, insurance policies and statutory instruments

  2. Financial documents such as accounts, performance reports and regulatory filings

  3. Medical content including research papers, instructions for devices and drugs, consent forms and documents related to clinical research.

  4. Manufacturing or product related content including operating instructions, safety guidance, food packaging, technical details and export documentation.

How do you decide whether back translation is necessary?

There are instances when back translation would be useful rather than entirely necessary. The professional translation, localisation and quality assurance services of a superior translation partner such as Word Connection may suffice. However, back translation would be an essential risk management tool when:

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  • The content relates to healthcare, insurance, financial services, legal documents, or instructions with safety implications.

  • The content relates to any products, services or practices that are regulated.

  • The accuracy of the translation is more important than its stylistic qualities.

  • It is necessary to verify advertising or promotional claims

Back translation is desirable when:

  • Poor or inappropriate translations could result in lost revenue

  • Erroneous translations could result in lost business opportunities

Back translation enables the owner of source material to remain in control. They may not understand the target language and so will have no ability to judge the quality of any outputs produced by their translation partner. Back translation provides peace of mind and ensures that businesses can trust the way their brand or product is portrayed. They can rely on translations of legal, technical and instructive content to be as accurate as is possible. Back translation is the right choice when any difference between the source and the translation really matters.

What is reconciliation?

Once a back translation has been performed, the translation is compared to the source material to identify any portions of text where the precise meaning of the original has been lost. In the case of text where accuracy is not essential, but the essence of the source material should be retained, an examination of the back translation can reveal areas for improvement. In either case, the content can then be edited to optimise the final output. This process is known as reconciliation. The project manager will usually provide the client with a reconciliation report that itemises the problems identified and how they have been addressed. They may also discuss options with the client before making amendments.

Back translation accuracy checks and machine translation

There are no real downsides to back translations of outputs produced by humans, other than the additional time and expense involved. When precision and quality are key, that expense would certainly be justified due to the potential impact of poor translations. However, the situation is very different with back translations performed by machine translation systems.

back translation

Laypeople and those seeking to minimise their translation budgets have been known to utilise back translations as a means of assessing the quality of machine translation systems or outputs created by their translation partners.  Unfortunately, this is a fool’s errand as it is impossible to deduce whether any issues that are identified have been caused by the inadequacy of the software or errors in the forward translation. Research has demonstrated that it is entirely possible to get an excellent back translation from a poor forward translation or a terrible back translation from a good forward translation. Back translation by machine is not useful in determining the efficacy of machine translation systems or the quality of a human translation. Neither is it an appropriate means of identifying whether a text is suitable for machine translation.

As natural language processing (NLP) is continuing to evolve and improve, technology may play a more useful role in back translation at some point in the future. NLP is the branch of artificial intelligence concerned with the understanding of written and spoken language. Considerable technological advancements have been achieved in recent years, but no computer system yet boasts the capabilities of human linguists in tackling back translation.

Which issues can back translation fail to identify?

There are problems with any forward translation that subsequent back translation could fail to reveal. Back translation will not provide an assessment of the creative or expressive quality of content. Translations should read naturally in the target language. Back translation will give no indication of the readability of outputs. Indeed, a back translation may give the false impression that content is clunky or difficult to read.

back translation

In addition, a back translation will usually fail to identify typos, spelling mistakes and grammatical errors in the forward translation. Some of these errors will become apparent when a seemingly strange word or phrase appears in the back translation. This will force the project manager tackling the reconciliation to explore the forward translation to understand what has caused the problem. But errors may remain undetected.

A back translation could fail to highlight ambiguities that appear in the translation if there are phrases that could be interpreted in more than one way. For example, consider the sentence “the man took the dog for a walk with a broken leg”. Was it the man or the dog that had a broken leg?


When accuracy is paramount, there is no substitute for back translation. In such situations, a back translation may be a regulatory requirement. Back translations can also be highly beneficial aspects of quality assurance, even when precision is less important. But the back translation process is an added expense that lengthens the time it will take to complete a project. There are instances when the expert work of a superior translation partner will produce outputs of the required quality. But it is difficult to put a price on risk management and peace of mind.

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#languageandcontext #LQA #projectmanager #translation

James Myatt

7 min read

Dec 9, 2021



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