Any time you translate material for a clinical trial, there is a good likelihood that you might find yourself in a situation where the client wants to resolve apparent discrepancies between the original text and the back-translation. The client has no way of doing so without referring to you. In most cases, all you need to do is assure them that your translation stands, and that it conveys the intended meaning as precisely as the target language will permit. But you need to do so in a credible, professional manner, avoiding as much as you can getting into a sparring match with the back-translator. If you have done your translation very carefully, your will rarely have to change anything.

What we have here is a perfect example of this kind of situation. Here is how I would reply to their request to confirm that the translation refers to “worried” and not “anxiety”:

I confirm that the translation is the most accurate and most common rendition of the word "worried." For example, it is the word used in the title of the famous book How to Stop Worrying and Start Living by Dale Carnegie. The word, as you can imagine, carries all the expected shades of meaning associated with the concept of worry, including anxiety, concern, and other near synonyms. It is not unusual for an Arabic-to-English translator to translate the word to "anxious" (or "anxiety" if the word is a noun). If you feel that the semantical difference is too wide, I can substitue a word or a phrase that has a narrower range of connotations, although, as always, I cannot guarantee how a back-translator might render it in English.

I would keep this paragraph in a safe place and use it whenever a similar disupte arises. Just substitute the relevant words for the current case at the time.

Now, for this particular case, if the client insists that they wish to substitue an expression that more narrowly reflects the concept of worry, I would suggest

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