The move towards living systematic reviews and living guidelines in healthcare: consideration of the possibilities and challenges for living qualitative evidence syntheses.

Over the past decade qualitative evidence synthesis (QES), a range of methods for synthesising qualitative research evidence, has become a valued form of evidence for guideline producers who wish to understand more about patient preference and acceptability of treatments. The surge in interest in living systematic reviews and the appearance of living guidelines as a response to the COVID-19 pandemic potentially weaken the value and usability of QES.There are currently no published methods for producing living QES, and if QES are to remain of worth to guideline producers then methods for the rapid, frequent updating of them will need to be developed. We discuss some of the similarities and differences between qualitative and quantitative evidence syntheses and highlight areas where development is needed if reviewers are to progress with living approaches to QES.