Agreement between crude and case-mix-adjusted p-charts in detecting indicator variations
| Case-mix adjusted limits* | |||||||
| <WL | =WL | WL–CL | =CL | >CL | Total | ||
| Crude | <WL | 53 | 1 | 0 | 0 | 0 | 54 |
| Limits* | =WL | 1 | 2 | 0 | 0 | 0 | 3 |
| WL–CL | 0 | 0 | 0 | 0 | 0 | 0 | |
| =CL | 0 | 0 | 0 | 0 | 1 | 1 | |
| >CL | 0 | 0 | 0 | 0 | 0 | 0 | |
| Total | 54 | 3 | 0 | 0 | 1 | 58 | |
↵* Each unit in the table represents the position of a data point on a recurrent laryngeal nerve palsy or hypocalcaemia control chart, according to five ordinal levels based on exact warning limits (WL, 95.45%) and control limits (CL, 99.73%), as follows: <WL (below the 95.45% limit), =WL (equal to the 95.45% limit), WL–CL (between the 95.45% and the 99.73% limits), =CL (equal to the 99.73% limit) and >CL (above the 99.73% limit).