I am undertaking a quantitative study using a questionnaire. At the end of the questionnaire there is a lined, blank page asking participants to write 'any other / further comments'. Are participants responses in this section considered qualitative or quantitative data? If they are qualitative, would this study then be regarded as a mixed-methods study, rather than quantitative? I would be interested in reading any articles that have used 'any further comments' as a qualitative component of a mixed - methods study.