Question: We heard about Stanford having a high case mix index. Can you explain what that means please?
Answer:The higher the hospital Case Mix Index the sicker the patients, the larger the surgeries, and with more resources having to be used to care for those challenging cases.
For example, Packard Children’s Hospital at Stanford has one of the highest Case Mix Indexes in the country.
As you know for Medicare patients a hospital is paid by DRG, or Diagnosis Related Group. For example, DRG 001 is Heart transplant or implant of heart assist system with major complications. The relative value for this DRG is 28, which means that the expected cost of taking care of that patient is 28 times the avergage cost of all Medicare inpatients across the country.
If all of a single hospital’s cases were DRG 001 then the Case Mix Index would equal 28. This is the highest relative value of all.
Please remember that for a particular DRG case/patient, the hospital is paid by multiplying this relative weight by the blended rate (a $ figure assigned to each hospital based on a variety of variables).
As another example, DRG 470 is knee replacement without complications which has a relative value of approximately 2. Taking the average of all of a hospital’s cases would give you overall Case Mix Index. Obviously some drg cases will have a relative weight less than 1 which will drag the CMI down.
Nationally, according to wikipedia the average hospital case Mix Index is 1.37 with a minimum of 0.58 and a max of 3.73 and a standard deviation of 0.31.
Best wishes for the Holidays!