Figure 1Comparison of statistical prediction models by Lift chart. 1Decision tree.
Figure 2Comparison of statistical prediction models by receiver operating characteristic curve. 1Decision tree.
Figure 3Prediction models in rehospitalization. Values are presented as number (%). No, nonrehospitalization; Yes, rehospitalization; OPD, out-patient department; ER, emergency room; ICD-10, 10th revision of the International Classification of Diseases.
Table 1.Demographic characteristics of subjects
|
All |
Nonrehospitalized |
Rehospitalized |
p-value (χ2 or t-test) |
Sex |
|
|
|
|
Male |
6096 (51.0) |
4133 (48.6) |
1963 (56.9) |
<0.001 |
Female |
5855 (49.0) |
4368 (51.4) |
1487 (43.1) |
|
Age |
|
|
|
|
0-9 |
763 (6.4) |
675 (7.9) |
88 (2.6) |
<0.001 |
10-19 |
364 (3.0) |
292 (3.4) |
72 (2.1) |
|
20-29 |
675 (5.6) |
523 (6.2) |
152 (4.4) |
|
30-39 |
1032 (8.6) |
805 (9.5) |
227 (6.6) |
|
40-49 |
1784 (14.9) |
1169 (13.8) |
615 (17.8) |
|
50-59 |
2440 (20.4) |
1596 (18.8) |
844 (24.5) |
|
60-69 |
2697 (22.6) |
1698 (20.0) |
999 (29.0) |
|
70+ |
2195 (18.4) |
1742 (20.5) |
453 (13.1) |
|
Residential regions |
|
|
|
|
Seoul |
6723 (56.3) |
4991 (58.7) |
1732 (50.2) |
<0.001 |
Gyeonggi/Incheon |
2785 (23.3) |
1914 (22.5) |
871 (25.2) |
|
Others |
2443 (20.4) |
1596 (18.8) |
847 (24.6) |
|
Total |
11 951 (100.0) |
8501 (100.0) |
3450 (100.0) |
|
Table 2.Clinical characteristics of subjects
|
All |
Nonrehospitalized |
Rehospitalized |
p-value (χ2 or t-test) |
Medical departments |
|
|
|
|
Internal |
7661 (64.1) |
5269 (62.0) |
2392 (69.3) |
<0.001 |
Surgical |
4290 (35.9) |
3232 (38.0) |
1058 (30.7) |
|
Premium medical treatment |
|
|
|
|
Yes |
11 118 (93.0) |
7893 (92.8) |
3225 (93.5) |
0.24 |
No |
833 (7.0) |
608 (7.2) |
225 (6.5) |
|
ICD-10 disease categories |
|
|
|
|
Neoplasms |
2173 (18.2) |
986 (11.6) |
1187 (34.4) |
<0.001 |
Endocrine, nutritional and metabolic diseases |
813 (6.8) |
642 (7.6) |
171 (5.0) |
|
Circulatory system |
1248 (10.4) |
1035 (12.2) |
213 (6.2) |
|
Respiratory system |
1240 (10.4) |
1045 (12.3) |
195 (5.7) |
|
Digestive system |
2465 (20.6) |
1589 (18.7) |
876 (25.4) |
|
Musculoskeletal sys- tem and connective tissue |
901 (7.5) |
790 (9.3) |
111 (3.2) |
|
Genitourinary system |
1114 (9.3) |
958 (11.3) |
156 (4.5) |
|
Symptoms, clinical findings, etc., else- where classified |
1997 (16.7) |
1456 (17.1) |
541 (15.7) |
|
No. of comorbidities |
1.5±1.1 |
1.6±1.2 |
1.4±0.9 |
<0.001 |
No. of accompanying treatments |
1.4±3.1 |
1.5±3.2 |
1.3±2.9 |
<0.001 |
Surgery |
|
|
|
|
Yes |
4451 (37.2) |
3375 (39.7) |
1076 (31.2) |
<0.001 |
No |
7500 (62.8) |
5126 (60.3) |
2374 (68.8) |
|
Total |
11 951 (100.0) |
8501 (100.0) |
3450 (100.0) |
|
Table 3.Health care utilization characteristics of subjects
|
All |
Nonrehospitalized |
Rehospitalized |
p-value (χ2 or t-test) |
Insurance |
|
|
|
|
National Health Insurance |
11 220 (93.9) |
7994 (94.0) |
3226 (93.5) |
0.002 |
Medical Aid |
525 (4.4) |
346 (4.1) |
179 (5.2) |
|
Other |
206 (1.7) |
161 (1.9) |
45 (1.3) |
|
Ward type |
|
|
|
|
Private room |
1144 (9.6) |
932 (11.0) |
212 (6.1) |
<0.001 |
Multi-bed room |
10 469 (87.6) |
7242 (85.2) |
3227 (93.5) |
|
Intensive care unit |
338 (2.8) |
327 (3.8) |
11 (0.3) |
|
Route of admission |
|
|
|
|
Out-patient department |
8368 (70.0) |
5565 (65.5) |
2803 (81.2) |
<0.001 |
Emergency room |
3583 (30.0) |
2936 (34.5) |
647 (18.8) |
|
Length of stay |
8.5±11.2 |
9.0±11.3 |
7.5±10.9 |
<0.001 |
No. of out-patient department visits |
14.7±20.0 |
11.7±17.5 |
22.0±22.5 |
<0.001 |
No. of admissions within previous 12 months |
2.5±3.4 |
1.8±2.2 |
4.4±4.8 |
<0.001 |
Utilization of emergency room within previous 12 months |
|
Yes |
1260 (10.5) |
828 (9.7) |
432 (12.5) |
<0.001 |
No |
10 691 (89.5) |
7673 (90.3) |
3018 (87.5) |
|
Total |
11 951 (100.0) |
8501 (100.0) |
3450 (100.0) |
|
Table 4.Comparison of statistical prediction models by root ASE and misclassification rate
|
|
Logistic regression |
Decision tree |
Neural network |
Root ASE |
Training data |
0.385 |
0.373 |
0.384 |
|
Validation data |
0.385 |
0.369 |
0.383 |
Misclassification rate |
Training data |
0.214 |
0.18 |
0.214 |
|
Validation data |
0.217 |
0.177 |
0.211 |