Back translation involves translating a text that has already been translated back into its original language again. The first translation and the second (back) translation are then compared and reconciled in order to test the quality and accuracy of the original translation. Because all languages have many different equally correct ways of expressing the same concept, a back translation cannot be expected to reproduce the exact wording of the original document, although a detailed comparison between the two texts should reveal any significant differences in meaning and therefore a possible error. However, it would still need to be decided whether the error was in the original translation or had been introduced in the back translation.
There are two steps involved in the process:
1 Back translation
• Should be done by an independent translator with equal knowledge of the subject who has not seen the original text
• Should be done as literally as possible
• Should not be done by a different supplier to avoid conflict of interest
• Should be done by another person
• There should be clear rules that differentiate between variations of style and differences of meaning
• If a difference of meaning is identified, it is necessary to determine whether the possible error is in the original forward translation or was introduced in the subsequent back translation.
• Differences need to be resolved
• Should identify basic factual errors (eg copy-typing figures, omissions)
• Does not remove the need for post-editing and proofreading the original translation
• Adds another layer of time and expense
• Adds another step and another person giving another opportunity for human error
• Needs yet another party/process to arbitrate between differences
• Reconciliation is an extremely skilled and responsible task
Translation followed by back translation and the reconciliation of the two texts produced is a thorough method to identify basic errors and omissions although it involves additional time and expense. The reconciliation should be done by skilled, experienced professionals who have been fully briefed by you, not by individuals for whom there might be a commercial advantage to finding faults.