Hello, everyone, Is it a common practice to add a 0.5 continuity correction for zero cells when measuring MD or SMD as the outcome measure? I have seen people use it when the outcome is measured as the RR or ROM, but not sure is it applicable when the outcome is measured as MD or SMD. Thank you, Tharaka
[R-meta] Adding a 0.5 continuity correction
2 messages · Tharaka S. Priyadarshana, Guido Schwarzer
Am 05.07.22 um 16:56 schrieb Tharaka S. Priyadarshana:
Hello, everyone, Is it a common practice to add a 0.5 continuity correction for zero cells when measuring MD or SMD as the outcome measure?
Hi Tharaka, For ratio measures like OR, RR or ROM one does not want to have a zero in the nominator or denominator. Accordingly, a continuity correction is typically used.? Measures based on differences like MD or SMD do not have this problem. library(meta) m.noincr <- metabin(rep(0, 2), 100:101, 1:2, 100:101, sm = "RR", ? incr = 0, overall = FALSE, overall.hetstat = FALSE) summary(m.noincr) m.withincr <- update(m.noincr, incr = 0.5) print(summary(m.withincr), ma = FALSE) Best, Guido Dr. Guido Schwarzer Institute of Medical Biometry and Statistics, Faculty of Medicine and Medical Center - University of Freiburg Postal address: Zinkmattenstr. 6a, D-79108 Freiburg Mail: sc at imbi.uni-freiburg.de Homepage: https://www.imbi.uni-freiburg.de/ ORCID iD: https://orcid.org/0000-0001-6214-9087 R-book: https://www.springer.com/gp/book/9783319214153