The variability of probability of that the length of stay is longer than the median by country. The variability of probability of that the length of stay is longer than the median by country. The black dots represent the logit of each hospital a, b) accounting only for cluster effects without covariates and c) accounting for cluster effects and covariates. The green dots represent the logit of each country. Logit is defined as the probability determined by logistic regression: logit(p)=log(p/1−p). Mamta Ruparel et al. ERJ Open Res 2016;2:00034-2015 ©2016 by European Respiratory Society