CCS DRG Assignment & Case Mix

Question 1

What does 'case mix index' (CMI) measure in a hospital?

Accepted Answer

The average DRG relative weight for all inpatient discharges, reflecting patient complexity

Answer

The total number of patients discharged per month

Answer

The percentage of Medicare patients versus commercial insurance patients

Answer

The ratio of surgical to medical admissions

Question 2

Which of the following secondary diagnoses would NOT qualify as a CC or MCC for MS-DRG assignment?

Accepted Answer

Essential hypertension (I10)

Answer

Acute respiratory failure

Answer

Stage 4 pressure ulcer

Answer

Septic shock

Question 3

What is a 'present on admission' (POA) indicator, and why is it required on inpatient Medicare claims?

Accepted Answer

It identifies whether each diagnosis was present when the patient was admitted, distinguishing hospital-acquired conditions from pre-existing ones

Answer

It identifies whether the physician was present at admission

Answer

It indicates the admission was an emergency rather than elective

Answer

It certifies the medical necessity of the inpatient admission

Question 4

A patient is admitted with pneumonia (MS-DRG 193, without CC/MCC) and is also found to have acute kidney injury. If the acute kidney injury qualifies as an MCC, the claim will be grouped to:

Accepted Answer

MS-DRG 191 - Pneumonia with MCC, higher relative weight

Answer

MS-DRG 193 - the MCC does not change simple pneumonia DRGs

Answer

MS-DRG 194 - Pneumonia with CC

Answer

MS-DRG 870 - the sepsis DRG, because AKI may indicate organ dysfunction

Question 5

What is the purpose of the Medicare Code Editor (MCE) in the DRG grouping process?

Accepted Answer

To identify invalid codes, age conflicts, sex conflicts, and manifestation code errors before DRG assignment

Answer

To assign the final DRG payment amount to each claim

Answer

To determine whether a diagnosis qualifies as a CC or MCC

Answer

To calculate the hospital's wage index adjustment

Question 6

Under IPPS, what is a 'transfer case' and how does it affect DRG payment to the transferring hospital?

Accepted Answer

The transferring hospital receives a per-diem payment, potentially less than the full DRG, unless the LOS meets or exceeds the national geometric mean

Answer

Transfer cases always receive full DRG payment at both facilities

Answer

Transfer cases are excluded from DRG grouping entirely

Answer

The receiving facility's DRG payment is reduced by 50%