This case concerns PROCPR 99S90 Extensive procedure - list created during the exporting process and how it is used across all national versions.
Use of PROCPR 99S90 was reviewed both from a clinical perspective and from the perspective of cross‑country differences.
There is no clear definition of “extensive procedure”. However, in casemix or DRG context one could define it as a procedure with high resource intensity that significantly increase expected costs, length of stay, complexity, and clinical risk. Its role is primarily grouping logic, not clinical description.
In the NordDRG system, PROCPR 99S90 is used to identify extensive procedures and, on that basis, to allow grouping to DRG 468/X  Rare or incorrect combination of diagnosis and extensive procedure/X. This distinction is necessary to separate cases that are not considered extensive, which are instead grouped to DRG 477/X Rare or incorrect combination of diagnosis and other procedures/X.
In addition, PROCPR 99S90 is used in the rules of following DRGs:
drg_comb
drg_text_comb
nat_ver

442X
Other OR procedures for injuries, w CC
est/lat/ice/fin/nor

443M
Other major OR procedures after injuries, w MCC
swe

443C
Other major OR procedures in general anaesthesia for injuries, w CC
swe

443N
Other major OR procedures in general anaesthesia for injuries, w/o CC
swe

443X
Other OR procedures for injuries, w/o CC
est/lat/ice/fin/nor

PROCPR 99S90 with minus (-) sing is not used in any DRG rules (minus sign is used in case to avoid grouping of case with a procedure code having PROCPR 99S90).
 
After having a look at the used on PROCPR 99S90, here are some observations:
There are procedure codes which are having OR value 0 or 2, yet having PROCPR 99S90. The codes are as follows: code_plus
text_plus
or_val
nat_ver*

JCSE35
Laprascopic operation on oesophageal atresia or congenital tracheo-oesophageal fistula
0
nor

NHSQ60
Revision of ampution or exarticulation of ankle or foot
0
ice/fin

FKSC61
Repair of mitral valve insufficiency by a transluminally inserted clip
2
fin/est

NAO10D
Termokoagulasjon i kolumna, CT-veiledet
2
nor

NAXA00
Heat coagulation of vertebral lesion
2
ice/fin/nor

NAXT60
Manipulation of the spine
2
ice/fin

*As Norwegian version is primarily maintained by Helsedirektoratet, there can be differences between the tables maintained in NDMS and HS.
2. There are cross-country differences among some codes:
code_plus
text_plus
or_val
nat_ver
Comment

LESF03
Posterior colporrhaphy
1
est/lat/ice/fin/nor
Not used in SWE version

LESF10
Colpoperineoplasty
1
est/lat/ice/fin/nor
Not used in SWE version

FZSA00
Total cardiopulmonary bypass in normothermia or moderate hypothermia at concurrent surgical procedure
1
swe
Used only in SWE version

KKSB11
Percutaneous endoscopic excision of retroperitoneal tumour
1
swe
Used only in SWE version

LESF40
Vaginal repair of enterocele
1
swe
Used only in SWE version

LESF41
Laparoscopic repair of enterocele
1
swe
Used only in SWE version

ZTXA40
Graft of synthetic skin substitute
1
swe
Used only in SWE version

Things to consider:
remove PROCPR 99S90 from procedure codes with OR 0 or 2, or change the OR value of procedure codes. harmonise the use of PROCPR 99S90 across countries, based on the principle that identical procedure codes are interpreted consistently regardless of country, whether as “extensive” or “non‑extensive". “non‑extensive. Revise all procedure codes from PROCPR 99S90 perspective (see attached a table of procedure plus codes with PROCPR 99S90 in 2027PL0 version).  Given that PROCPR text Extensive procedure - list created during the exporting process was used during the transition of definition tables from FoxPro to NDMS in 2018, I suggest to change the text: Extensive procedure - list created during the exporting process -> Extensive procedure. This case is meant to be discussed in next EG Spring meeting. Any comments or views on this issue are welcome any time.