We are conducting a systematic review with three authors. Our common language is English, however between us we also speak three other languages, but there is only one person in the group that speaks any of the other languages. If we don't include papers in those other languages, we risk bias from only including English papers; but if we do include papers in any of those other languages we risk bias from only one author reviewing those papers.
Does anyone else have experience of this problem? How do we address the trade-off between publication language bias and reviewer bias?
Thanks in advance!