Table 3.
A comparison of actual patient outcomes using four scoring systems. Numbers of cases for “events + alarms from the system”, “non-events + no alarm”, “events + no alarm” and “non-events + alarm” are reported for the unseen test data (total number of observations = 36,769 across 4 months in 4 centres), of which 340 were adverse events and 36,429 were non-events. Percentages in the last two columns were computed as the % of total no-alarms followed by SAEs and that of total alarms followed by SAEs, respectively. Youden’s thresholds (cut-off values) for LogEWS2, DyniEWS.simplified and DyniEWS that maximised the sum of sensitivity and specificity were derived from internal validation.
| Methods | Event & alarm | Non-event & no-alarm | Event & no-alarm | Non-event & alarm | Total alarm | Total no-alarm |
|---|---|---|---|---|---|---|
| N (% 340 expected cases) | N (% 36,429 expected cases) | N (% total no-alarms) | N (% total alarms) | N | N | |
| NEWS (cut-off = 3) | 242(71) | 22,827(63) | 98(0.4) | 13,602(98) | 13,844 | 22,925 |
| NEWS (cut-off = 5) | 140(41) | 32,644(90) | 200(0.6) | 3785(96) | 3925 | 32,844 |
| NEWS (cut-off = 7) | 63(19) | 35,624(98) | 277(0.8) | 805(93) | 868 | 35,901 |
| LogEWS2 (cut-off = 1.01%) | 207(61) | 27,648(76) | 133(0.5) | 8781(98) | 8918 | 27,851 |
| DyniNEWS.simplified (cut-off = 1.14%) | 211(62) | 29,422(81) | 129(0.4) | 7007(97) | 7218 | 29,551 |
| DyniEWS (cut-off = 0.97%) | 233(69) | 28,127(77) | 107(0.4) | 8302(97) | 8535 | 28,234 |