Fig. 4

Standardised Mortality Ratios (SMR) by hospital trust for patients with HA-AKI in the 5 largest treatment specialty groups in our cohort

Footnote: Funnel plot of SMRs by hospital Trust in the top five largest specialties. Each patient in our cohort was given an individual expected probability of dying, based on the coefficients from the logistic regression model that corresponded to their individual risk factors. The expected probability for each patient was summed across all patients at each Trust to calculate the overall expected number of deaths at that Trust. SMRs were then calculated as the observed number of deaths divided by the expected number of deaths. Owing to the large amount of variation between Trusts, the funnel plot is presented with 95% and 99.8% confidence limits, inflated using an additive random effects model with a 10% trim for overdispersion