RT Journal Article SR Electronic T1 Dealing with categorical risk data when extracting data for meta-analysis JF BMJ Evidence-Based Medicine JO BMJ EBM FD BMJ Publishing Group Ltd SP bmjebm-2020-111649 DO 10.1136/bmjebm-2020-111649 A1 Kathryn S Taylor A1 Kamal R Mahtani A1 Jeffrey K Aronson YR 2021 UL http://ebm.bmj.com/content/early/2021/01/13/bmjebm-2020-111649.abstract AB