Table 3.
Characteristics of the development and validation sets.
| Characteristicsa | Development sets (n=1004) | Validation sets (n=191) | |||||||
|
|
Case (n=209) | Control (n=795) | Case (n=39) | Control (n=152) | |||||
| Age (years), mean (SD) | 61.43 (13.86) | 61.85 (14.39) | 66.10 (13.13) | 63.71 (14.97) | |||||
| Sex, n (%) | |||||||||
|
|
Male | 159 (76.1) | 522 (65.7) | 31 (79.5) | 100 (65.8) | ||||
|
|
Female | 50 (23.9) | 273 (34.3) | 8 (20.5) | 52 (34.2) | ||||
| Surgery, n (%) | |||||||||
|
|
No | 52 (24.9) | 294 (37.0) | 5 (12.8) | 30 (19.7) | ||||
|
|
Yes | 157 (75.1) | 501 (63.0) | 34 (87.2) | 122 (80.3) | ||||
| Intubation location, n (%) | |||||||||
|
|
Emergency room | 26 (12.4) | 61 (7.7) | 7 (17.9) | 24 (15.8) | ||||
|
|
Intensive care unit (ICU) | 149 (71.3) | 541 (68.1) | 27 (69.2) | 107 (70.4) | ||||
|
|
Operating room | 15 (7.2) | 94 (11.8) | 2 (5.1) | 13 (8.6) | ||||
|
|
Ward or others | 19 (9.1) | 99 (12.5) | 3 (7.7) | 8 (5.3) | ||||
| Reason for ICU admission, n (%) | |||||||||
|
|
Respiratory | 36 (17.2) | 237 (29.8) | 2 (5.1) | 24 (15.8) | ||||
|
|
Cardiovascular | 30 (14.4) | 108 (13.6) | 11 (28.2) | 29 (19.1) | ||||
|
|
Perioperative | 36 (17.2) | 237 (29.8) | 2 (5.1) | 24 (15.8) | ||||
|
|
Others | 28 (13.4) | 109 (13.7) | 3 (7.7) | 32 (21.1) | ||||
| Recording frequency, mean (SD) | |||||||||
|
|
Confusion Assessment Method for the Intensive Care Unit (CAM-ICU) | 0.65 (0.63) | 0.55 (0.53) | 1.15 (0.43) | 0.99 (0.45) | ||||
|
|
Richmond Agitation-Sedation Scale (RASS) | 3.75 (5.93) | 2.02 (2.84) | 3.69 (3.64) | 2.28 (2.72) | ||||
|
|
Glasgow Coma Scale (GCS) | 3.38 (1.93) | 3.52 (2.16) | 2.59 (0.85) | 2.91 (1.74) | ||||
|
|
Upper-limb motor power | 3.01 (1.79) | 3.18 (2.19) | 2.54 (1.05) | 2.79 (1.77) | ||||
|
|
Lower-limb motor power | 3.01 (1.79) | 3.17 (2.19) | 2.51 (1.05) | 2.79 (1.77) | ||||
|
|
Use of physical restraint | 1.00 (1.07) | 0.61 (0.84) | 0.95 (0.69) | 0.59 (0.67) | ||||
| Nearest value of CAM-ICU, n (%) | |||||||||
|
|
Negative | 49 (23.4) | 148 (18.6) | 14 (35.9) | 48 (31.6) | ||||
|
|
Positive | 59 (28.2) | 151 (19.0) | 24 (61.5) | 57 (37.5) | ||||
|
|
Unable to access | 18 (8.6) | 135 (17.0) | 1 (2.6) | 38 (25.0) | ||||
|
|
Missing | 83 (39.7) | 361 (45.4) | 0 (0) | 9 (5.9) | ||||
| Nearest value of RASS, n (%) | |||||||||
|
|
less than –2 | 20 (9.8) | 213 (26.9) | 2 (5.6) | 42 (28.2) | ||||
|
|
–2 or –1 | 31 (15.1) | 166 (20.9) | 7 (19.4) | 43 (28.9) | ||||
|
|
0 | 51 (24.9) | 190 (24.0) | 9 (25.0) | 26 (17.4) | ||||
|
|
+1 or +2 | 60 (29.3) | 163 (20.6) | 4 (11.1) | 25 (16.8) | ||||
|
|
more than +2 | 43 (21.0) | 61 (7.7) | 14 (38.9) | 13 (8.7) | ||||
| Nearest value of GCS, mean (SD) | |||||||||
|
|
Eye response | 3.38 (0.93) | 2.93 (1.15) | 3.54 (0.68) | 3.04 (1.08) | ||||
|
|
Motor response | 5.49 (1.19) | 4.86 (1.71) | 5.79 (0.52) | 5.05 (1.60) | ||||
| Nearest value of upper-limb motor power, mean (SD) | |||||||||
|
|
Right | 3.70 (1.31) | 3.04 (1.62) | 4.00 (0.76) | 2.99 (1.59) | ||||
|
|
Left | 3.72 (1.26) | 3.05 (1.62) | 4.10 (0.60) | 3.00 (1.59) | ||||
| Nearest value of lower-limb motor power, mean (SD) | |||||||||
|
|
Right | 3.00 (1.48) | 2.59 (1.62) | 3.44 (1.05) | 2.59 (1.54) | ||||
|
|
Left | 3.03 (1.48) | 2.62 (1.61) | 3.44 (1.05) | 2.62 (1.56) | ||||
| Nearest value of use of physical restraint, n (%) | |||||||||
|
|
No | 84 (40.2) | 460 (57.9) | 13 (33.3) | 79 (52.0) | ||||
|
|
Yes | 125 (59.8) | 335 (42.1) | 26 (66.7) | 73 (48.0) | ||||
| Work shift, n (%) | |||||||||
|
|
Day (7 AM to 3 PM) | 78 (37.3) | 296 (37.2) | 16 (41.0) | 61 (40.1) | ||||
|
|
Evening (3 PM to 11 PM) | 49 (23.4) | 242 (30.4) | 13 (33.3) | 38 (25.0) | ||||
|
|
Night (11 PM to 7 AM) | 82 (39.2) | 257 (32.3) | 10 (25.6) | 53 (34.9) | ||||
aFor time-series features, the recording frequency over 8 hours prior to the time point and the nearest value to the time point were derived.