[Air-l] validity of the research

hello :) Introducing qualitative research in the seminar, I was asked a question about the validity of online researches: how may we trust the results, when we don't get non-verbal information and how can we be sure whether the respondent says the truth or lies... I usually use additional methods for validation, such as observation or interviews IRL, but in some cases I (and possibly other researchers too) just trust, what my respondents say and build my conclusions on their words... so I wanted to ask, how do you deal with the question of validity doing the research online? Regards Aurelija Dagilyte