%0 Journal Article %A Morris, TP %A van Smeden, M %D 2022 %F discovery:10134915 %I Elsevier BV %J Journal of Clinical Epidemiology %K Causal analysis, Sample size, Power, Meta-analysis, Planning %P 261-283 %T Causal analyses of existing databases: The importance of understanding what can be achieved with your data before analysis (commentary on Hernán) %U https://discovery.ucl.ac.uk/id/eprint/10134915/ %V 142 %Z This version is the author accepted manuscript. For information on re-use, please refer to the publisher’s terms and conditions.