Back translation is the process of translating a document that has already been translated into a foreign language back into the original language, often without stylistic fine-tuning, by a translator who has not seen the original text

Many companies, especially pharmaceutical companies conducting clinical trials, require back translation in order to check the documents have been accurately translated into the target language since even the smallest of errors can pose huge problems in this field.

The translator performing a back translation must have thorough knowledge and understanding of the subject matter in order to properly back translate professional terminology, commonly used words and different synonyms.