1. Rare event research: is it worth it?
M.J. Barrington, B.D. Sites 
British Journal of Anaesthesia 
Volume 114, Issue 5, Pages (May 2015)
DOI: /bja/aev101
Copyright © 2015 The Author(s) Terms and Conditions

2. Fig 1
A p chart demonstrating performance around opioid utilization in a theoretical healthcare institution. The y-axis is the proportion of patients receiving any opioids during their ambulatory visit. Increased opioid use should be considered poorer performance. The x-axis is time. The solid centerline represents the grand mean of the means from the individual time periods and the dashed lines represents the control limits based on approximately three standard deviations above and below the mean of the means. In this case, the intervention was a clinical transition from peripheral regional anaesthesia to general anaesthesia for hand surgery. The 8 points above the average and enclosed by the circle indicate that performance degraded after this change in clinical practice. This information is helpful in guiding a microsystem change at this hypothetical institution.
British Journal of Anaesthesia  , DOI: ( /bja/aev101)
Copyright © 2015 The Author(s) Terms and Conditions