This SAS program reads in a list of ICD-9-CM codes and calculates the Combined Comorbidity Score, which was developed based on conditions included in the Charlson Index and the Elixhauser comorbidity system, and which shows better ability to discriminate mortality than either component score.

Reference:

Gagne JJ, Glynn RJ, Avorn J, Levin R, Schneeweiss S. A combined comorbidity score predicted mortality in elderly patients...