Back translations

Back translations – what are they, and are they useful?

A Google search for the definition of ‘back translation’ will be sure to yield plenty of hits. Most are published by translation service providers offering their own view on the process, but none appear to comment on the accuracy/cost efficiency of this method of quality assurance.

Back translation is one of several possible quality control tools, and is defined by Dora Wirth (Languages) Ltd. as follows:

‘A source text is translated into a target (forward) language and the target language text is translated back into the source language by an independent translator who has not had sight of the source text and will therefore provide an unbiased rendition of the meaning of the forward translation for quality-control purposes.’

Thus a back translation is a good way to allow a non-native speaker of the target language to check a forward translation for errors or omissions and to ensure, more importantly, that the forward translation gets across the essence of the source text.

Let us imagine that you have commissioned the translation of an informed consent form from English into Arabic, but you don’t speak Arabic, and you are unable to have the translation reviewed by a trusted native speaker.  This is a patient-facing document, so you need to be sure your text has been rendered correctly. How can you be sure you have a quality forward translation?

Back translation: A translator fluent in the language of the source text (Arabic) should be briefed to provide a faithful translation of the forward translation back into English.

NB: At no point in the process should the back translator be shown the original English source text, as this may introduce bias. This includes any prior involvement in the project.

Reconciliation: The resulting English back translation may then be compared against the original English source text to highlight any errors, deviations or different interpretations. If there are discrepancies, the forward translator should be contacted to check if these errors occurred in the Arabic forward translation.

In order to arrive at an agreed final forward translation, the forward and back translation should be amended in turn until you are satisfied that the forward translation contains the correct information.

NB: Discussion of discrepancies between back translation and source text and the interpretation rendered by the forward translation can be a lengthy process.

In addition, a forward translator could be tempted to adjust their translation for the purpose of an enhanced back translation, when discrepancies between back translation and original source text are followed up. This is NOT the idea. Forward translators should be encouraged to stand by their translation if they feel they have rendered the essence of the meaning of the source text and their translation reads well. Not all linguistic concepts, translated through a word-by-word rendition, will emerge from the back translation in the same way.

Costs: The back translation will usually be charged by the number of words in the forward translation. Reconciliation between the two versions will usually be charged on translator time. If an independent back-translation is required (i.e. the service provider has not seen the original source text), you may amend the back translation and ask the service provider to update the forward translation accordingly. This will normally be charged on a time basis.


  • Ample time should be allowed for the resolution of any deviations highlighted by the back translation, particularly if the document is lengthy. This does not make back translations ideal when deadlines are tight.
  • Back translations can be used either for information purposes or for quality control purposes. You should alert your language services provider if you plan to use a back translation as a document in its own right – translators will usually provide a more literal back translation than would be expected of a forward translation.
  • A back translation will point to errors in the forward translation such as omissions and misinterpretations. However, it will not necessarily flag up purely linguistic issues in the forward translation such as poor style, spelling and grammatical errors or incorrect technical terminology. These aspects should be taken care of through a robust quality control procedure for the forward translation.


So, given plenty of time back translations can be just one of the tools to ensure the accuracy of a forward translation.

What are the differences in doing a ‘normal’ translation as opposed to a ‘back translation’?

For a back translation, a more literal approach is taken. For example:

Your document is for submission to the EMA and says:

    • Keep out of the sight and reach of children.

The German EMA template translates this as:

    • Arzneimittel für Kinder unzugänglich aufbewahren.

The (literal) back translation might read:

    • Store medicine so as not to be accessible to children.

In this way, a back translation would give you a more accurate picture of exactly what the forward translation says. This is not to say, however, that the German translation is incorrect when reconciling the back translation with the original source text.


Before deciding on back translation, get in touch to discuss whether or not this strategy will benefit your project and consider requesting a full review of your translation by a second specialist translator instead (provided as standard by Dora Wirth (Languages) Ltd.).