The TRICARE DRG-based payment
system is modeled on the Medicare PPS. Although many of the procedures
in the TRICARE DRG-based payment system are similar or identical
to the procedures in the Medicare PPS, the actual payment amounts,
DRG weights, and certain procedures are different. This is necessary
because of the differences in the two programs, especially in the
beneficiary population. While the vast majority of Medicare beneficiaries
are over age 65, TRICARE beneficiaries are considerably younger
and generally healthier. Moreover, some services, notably obstetric
and pediatric services, which are nearly absent from Medicare claims
comprise a large part of TRICARE services.
3.2.2 Assignment Of Discharges To
DRGs
TRICARE uses a “Grouper” program
to classify specific hospital discharges within DRGs so that each
hospital discharge is appropriately assigned to a single DRG based
on essential data abstracted from the inpatient bill for that discharge.
The TRICARE Grouper is developed by Health Information Systems,
3M Health Care, and is based on the Centers for Medicare and Medicaid
Services (CMS) Grouper, but it also incorporates the PM-DRGs, and
DRGs 899 and 898.
3.2.2.1 The Medicare Code Editor (or
other similar editor programs) is an integral part of the CMS Grouper and
serves two functions. It helps to ensure that the claim discharge
data is accurate and complete, so that it can be correctly grouped
into a DRG. It also “edits” the claims data to identify cases which
may not meet certain coverage requirements or which might involve
inappropriate services. Contractors are not required to use any
“Editor” program, but it is recommended since the first function
will facilitate claims processing, and the second function may be
useful in assessing coverage under TRICARE.
3.2.2.2 The classification of a particular
discharge is based on the patient’s age, sex, principal diagnosis
(that is, the diagnosis established, after study, to be chiefly
responsible for causing the patient’s admission to the hospital),
secondary diagnoses, procedures performed, and discharge status.
(Contractors are required to use the expanded diagnosis and procedure
code fields.) For neonatal claims (other than normal newborns),
it also is based on the newborn’s birth weight, surgery, and the
presence of multiple, major and other problems which exist at birth.
For services provided before the mandated date, as directed by Health
and Human Services (HHS), for International Classification of Diseases,
10th Revision (ICD-10) implementation, the birth weight is to be
indicated through use of a fifth digit on the neonatal International
Classification of Diseases, 9th Revision, Clinical Modification
(ICD-9-CM) diagnosis code. For services provided on or after the
mandated date, as directed by HHS, for ICD-10 implementation, the
birth weight is to be indicated through use of a sixth digit on
the neonatal ICD-10-CM diagnosis code.
3.2.2.2.1 The contractor shall give precedence
to the narrative and revise the numerical code accordingly in situations
where the narrative diagnosis on the DRG claim does not correspond
to the numerical diagnosis code. Contractors are not required to
make this comparison on every claim. Precedence should be given
to the narrative code in those cases where a difference is identified
as the result of editing, prepayment review, or other action that would
identify a discrepancy. If an adjustment is subsequently necessary
because the numerical code was, in fact, correct, the adjustment
should be submitted with a reason for the adjustment code indicating
that there was no contractor error.
3.2.2.2.2 It is the hospital’s responsibility
to submit the information necessary for the contractor to assign
a discharge to a DRG.
3.2.2.2.3 The contractor shall develop
the claim for the additional information when the discharge data
is inadequate (i.e., the contractor is unable to assign a DRG based
on the submitted data).
3.2.2.2.4 In some cases the “admitting
diagnosis” may be different from the principal diagnosis.
3.2.2.2.5 For neonatal claims only (other
than normal newborns), the following rules apply.
• If a neonate (patient age 0
- 28 days at admission) is premature, the appropriate prematurity
diagnosis code must be used as a principal or secondary diagnosis.
• Where a prematurity diagnosis
code is used, a fifth digit value of 0 through 9 must be used in
the principal or secondary diagnosis to specify the birth weight.
If no fifth digit is used, the Grouper will ignore that diagnosis code
and the claim will be denied.
• If a neonate is not premature,
a prematurity diagnosis code must not be used. The Grouper will
automatically assign a birth weight of “> 2,499 grams” and assign
the appropriate PM-DRG. If the birth weight is less than 2,500 grams,
the birth weight must be provided in the “remarks” section of the
CMS 1450 UB-04.
• If there is more than one birth
weight on the claim, the Grouper will assign the claim to the “ungroupable”
DRG, and the claim will be denied.
• All claims for beneficiaries
less than 29 days old upon admission (other than normal newborns)
will be assigned to a PM-DRG, except those classified to DRGs 103,
480, 495, 512, and 513. DRGs for these descriptions can be found
at
http://www.health.mil/rates.
3.2.2.3 Each discharge will be assigned
to only one DRG (related, except as provided in
paragraphs 3.2.2.4 and
3.2.2.5,
to the patient’s principal diagnosis) regardless of the number of
conditions treated or services furnished during the patient’s stay.
3.2.2.4 The
contractor shall develop the claim to assure that the data is not
the result of miscoding by either the contractor or the hospital
when the discharge data submitted by a hospital show a surgical
procedure unrelated to a patient’s principal diagnosis. Where the
procedure and medical condition are supported by the services and
the procedure is unrelated to the principal diagnosis, the claim
shall be assigned to the DRG, Unrelated OR Procedure.
3.2.2.5 The
contractor shall review the claim to determine if other diagnoses
or procedures which were rendered concurrently are covered when
the discharge data submitted by a hospital results in assignment
of a DRG which may need to be reviewed for coverage (e.g., abortion
without dilation and curettage, which does not meet the TRICARE
requirements for coverage).
3.2.2.5.1 The contractor shall, if other
covered services were rendered, change the principal diagnosis to
the most logical alternative covered diagnosis, delete the abortion
diagnosis and procedure from the claim so that it does not result
in a more complex DRG, and regroup the claim.
Example: If a claim is grouped into
the DRG for an abortion and the abortion is not covered, but a tubal
ligation was performed concurrently, the contractor should change
the principal diagnosis to that for the tubal and delete the abortion
from the procedures performed. If no covered services were rendered, the
claim must be denied, and all related ancillary and professional
services which are submitted separately must also be denied.
3.2.2.5.2 The contractor shall develop
for medical necessity only if the principal diagnosis is generally
not covered but potentially could be. Deletion of a diagnosis or
procedure is required only when the principal diagnosis or procedure
is not covered. Contractors are not normally required to review
all diagnoses and procedures to determine their coverage.
3.2.2.5.3 The only exception to the above
paragraph is for abortions. Since abortions are statutorily excluded from
coverage except for pregnancies resulting from rape, incest or if
the life of the mother is endangered, the contractor shall ensure
that payment is not affected by a noncovered abortion diagnosis
or procedure whether it is principal or secondary. In all cases
where payment would be affected, the abortion data is to be deleted
from the claim.