The OpenSAFELY Collaborative, Wong, A., Tomlinson, L., Brown, J., Elson, W., Walker, A., Schultze, A., Morton, C., Evans, D., Inglesby, P., Mackenna, B., Bhaskaran, K., Rentsch, C., Powell, E., Williamson, E., Croker, R., Bacon, S., Hulme, W., Bates, C., Curtis, H., Mehrkar, A., Cockburn, J., McDonald, H., Mathur, R., Wing, K., Forbes, H., Eggo, R., Evans, S., Smeeth, L., Goldacre, B. & Douglas, I. 2021, 'Association between warfarin and COVID-19-related outcomes compared with direct oral anticoagulants: population-based cohort study', Journal of Hematology and Oncology, 14, article no: 172. https://doi.org/10.1186/s13045-021-01185-0