Table 3: Comparison of Mortality Rates in the Development and the Validation Populations*

Mortality p Value
Development Population Validation Population
Overall initial risk class 108/472 (22.9%) 148/511 (29.0%) 0.03
I 6/153 (3.9%) 10/122 (8.2%) 0.13
II 63/253 (24.9%) 62/272 (22.8%) 0.57
III 39/66 (59.1%) 76/117 (65.0%) 0.43
Adjustment in each initial risk class
Class I
Adjustment risk score < or =2 points
Adjustment risk score > 2 points

2/145 (1.4%)
4/8 (50%)

4/104 (3.9%)
6/18 (33.3%)

0.24
0.66
Class II
Adjustment risk score = 0 point
Adjustment risk score = 1 or 2 points
Adjustment risk score > 2 points

3/149 (2.0%)
24/62 (38.7%)
36/42 (85.7%)

4/131 (3.1%)
8/62 (12.9%)
50/79 (63.3%)

0.71
0.001
0.01
Class III
Adjustment risk score < or = 2 points
Adjustment risk score > 2 points

25/51 (49%)
14/15 (93.3%)

43/77 (55.8%)
33/40 (82.5%)

0.45
0.42

* Data are presented as No. (%).