OBJECTIVES: The objective of this study was to determine whether dual back-translators improve the translation process for Patient Report Outcomes (PRO). METHODS: Four (4) PROs were translated using dual back-translators. The two back-translators worked independently, possessing no knowledge of the other’s back-translation. The translated PROs were: a physical assessment questionnaire containing 1507 words with medical terminology, a physical assessment questionnaire with simple terminology containing 593 words, a COPD questionnaire containing medical concepts with 713 words, and a cancer treatment questionnaire containing colloquial terminology and 403 words.  Instances of the following scenario were tallied during analysis: one back-translation accurately reflected the source, the other back-translation inaccurately reflected the source, but revealed an error in the forward translation. The same PROs were analyzed again, focusing only on one of the back-translators to compare the number of forward translation revisions that occur when using a single back-translator.  RESULTS: After analysis, 184 forward translation revisions occurred when using dual back-translators. 11 out of the 184 were a revision to a forward translation where one back-translation was correct despite the other back-translation being incorrect. This occurred 4 times amongst Slavic family languages, 3 times amongst Indian languages, 3 times amongst Southeast Asian languages, and once with Chinese. No such revisions occurred amongst Latin and Germanic language families. After analysis of the translated PROs with just one back-translator, a total of 180 forward translation revisions occurred. CONCLUSIONS: A second back-translation improves the translation process if the readability of the text of higher difficulty, and if Slavic, Asian and Indian language translations are required. However, the low number of revisions resulting from one incorrect back-translation, while using dual back-translators, demonstrates that one back-translator is acceptable. Since dual back-translators revealed the need for only 4 more forward translation revisions than the single back-translator, the quality output is similar.