Fig 1. Change in outlier status of comorbidity adjusted HSMRs without and with severity adjustment.

--- 95% Control Limits--- 99% Control Limits Stroke severity adjustment changes health service from an outlier to a non-outlier designated with a green diamond Stroke severity adjustment changes health service from a non-outlier to an outlier designated with a red square Alert signal “downgraded” from an 99% to 95% control limit outlier with stroke severity adjustment designated with a green circle. Alert signal “upgraded” from an 95% to 99% control limit outlier with stroke severity adjustment designated with a red circle.