The Charlson Comorbidity Index - Text Mining Techniques for Healthcare Provider Quality Determination - page 197

Figure 25. Lift function for mortality prediction

Table 31. Predicted versus actual mortality for cardiovascular surgery using the Charlson index to
define patient severity

Hospital Actual Mortality Predictive Mortality

1 1.23 23.08

2 0 0

3 4.46 41.07

4 0.79 26.88

5 1.14 26.14

6 0.57 0

7 3.53 0

8 2.22 0

9 1.28 24.36

10 3.13 70.83

nique that uses all of the diagnosis codes to define patient risk. This technique requires the use of text
analysis. We will compare the Charlson Index to other severity indices in subsequent chapters.

dIscussIon

A risk adjustment index can be defined through consensus or through statistical analysis or both. In this
chapter, we discussed the Charlson Index in detail, and defined a new index that appears to have better
features than the Charlson Index. One of the failings of the Charlson Index is that once it was defined,
it was not updated. The need for an update is most apparent in the high weight given to HIV, which did