New Zealand Casemix Framework for Publicly- Ministry of Health

1、1Version 14 New Zealand Casemix Framework For Publicly Funded Hospitals including WIESNZ08 Methodology and Casemix Purchase Unit Allocation for the 2008/09 Financial Year Specification for Implementation on NMDS Authors: The NPP Casemix Cost Weights Project Group 2Version 14 Table of Contents 1PURPO

2、SE OF THIS DOCUMENT.4 2CHANGES EFFECTED IN THIS VERSION.4 3INTRODUCTION .4 3.1BACKGROUND.5 3.2RECENT HISTORY OF CHANGES TO THIS CASEMIX FRAMEWORK.5 3.2.1Changes from WIES11C to WIESNZ08.5 3.2.2New Health Specialty Codes.6 3.2.3Changes from WIES11B to WIES11C .6 3.2.4Changes from WIES11A to WIES11B.7

3、 3.2.5The Casemix Funding Framework in 2008/09.7 3.3AREAS FOR CHANGE IN THE FUTURE.7 3.3.1Maternity/Obstetrics Purchasing.8 3.3.2Facilities used in DHB subcontracting.8 3.3.3Simultaneous transplants of the kidney and pancreas.8 3.3.4Scoliosis Spinal Implants and Spinal Cord Stimulators.8 3.3.5Cancel

4、led procedures .9 4WIESNZ08 CALCULATION .9 4.1DERIVED VARIABLES REQUIRED IN CALCULATION.9 4.1.1Length of Stay .9 4.2DRG REALLOCATIONS.9 4.2.1Adjustment for Peritoneal Dialysis.10 4.2.2Adjustment of medical AR-DRGs with radiotherapy.10 4.2.3Adjustment for Carotid Stenting.10 4.2.4Adjustment for D06Z:

5、 Sinus, Mastoid, and Complex Middle Ear Procedures.10 4.2.5Adjustment for K04Z: Major Procedures for Obesity .11 4.2.6All other AR-DRGs .11 4.3ADJUSTED MECHANICAL VENTILATION DAYS.11 4.3.1DRGs excluded from mechanical ventilation days.11 4.3.2Calculation of mechanical ventilation days from hours.11

6、4.4GENERAL CALCULATION.12 4.4.1Calculating WIESNZ08.14 4.4.2Copayment for Mechanical Ventilation.15 4.4.3Copayment for AAA and ASD.16 4.4.4Base WIES.16 4.4.5Final WIES weight.19 5PURCHASE UNIT ALLOCATION.19 5.1DERIVED VARIABLES REQUIRED IN ALLOCATION.19 5.1.1Patients Age.19 5.1.2Length of Stay .19 5

7、.2EXCLUSIONS FROM CASEMIX PURCHASING.19 5.2.1Base purchase publicly funded events (EXCLU).20 5.2.2Note on Historical Purchaser exclusions .20 5.2.3Publicly Funded Agencies .21 5.2.4Error DRGs.22 5.2.5Non-Treated Patients (Boarders- BOARDER or cancelled operations-CANC_OP).22 5.2.6Mental Health Event

8、s (EXCLU).22 5.2.7Disability and Health of Older People Events.23 5.2.8Maternity Secondary and Tertiary Facility Table.23 5.2.9Secondary Tertiary Maternity and Neonatal Events .24 5.2.10Birth weight.24 5.2.11Postnatal Early Intervention Events (W03012).24 5.2.12Neonatal Inpatient Casemix (PU=W06.03)

9、.24 3Version 14 5.2.13Amniocentesis (W03005) .25 5.2.14Chorion Villis Sampling (W03006).25 5.2.15Rhesus Isoimmunisation and other isoimmunisation. (W03007).25 5.2.16Breast feeding / Lactation disorders associated with childbirth (W03010).26 5.2.17Maternity Casemix.26 5.2.18Primary Maternity Events (

10、W02007,W02008, W02009, W02010, W02011) .26 5.2.19Some Transplants (T0103, T0106, T0111, T0113).27 5.2.20Some Spinal Injuries (S50001 or S50002).28 5.2.21Surgical Termination of Pregnancy - 2nd trimester (S30009).28 5.2.22Surgical Termination of Pregnancy - 1st trimester (S30006).28 5.2.23Peritoneal

11、Dialysis (M60005) .28 5.2.24Renal Haemodialysis (M60008) .28 5.2.25Sameday Chemotherapy not for cancer (MS02008).28 5.2.26Sameday Chemotherapy for cancer (MS02009, M30020, M54004).29 5.2.27Sameday Radiotherapy (M50005).29 5.2.28Sleep Apnoea Assessment (MS02010) .29 5.2.29Note on Anaesthesia coding.2

12、9 5.2.30Lithotripsy (S70006).29 5.2.31Colposcopies (NCSP-20).30 5.2.32Cystoscopies (MS02004).30 5.2.33Aggregated Gastroenterology codes .31 5.2.34Endoscopic retrograde cholangiopancreatography (ERCPs), Endoscopic retrograde cholangiography (ERC), and Endoscopic retrograde pancreatography(ERP) (MS020

13、06) .31 5.2.35Colonoscopies (MS02007).32 5.2.36Gastroscopies (MS02005).32 5.2.37Bronchoscopies (MS02003).33 5.2.38Day Case Blood Transfusions (MS02001).33 5.2.39Designated Hospital for Casemix Revenue .33 5.3MAPPING OF HEALTH SPECIALITY CODES TO CASEMIX PUS.36 5.4IDENTIFYING DHB CASEMIX-FUNDED EVENT

14、S FOR INTER-DHB INPATIENT FLOW CALCULATIONS.38 APPENDIX 1: TABLE OF 08/09 FY DRG COST WEIGHTS AND ASSOCIATED VARIABLES FOR CALCULATING WIESNZ08.40 6.1VARIABLE NAMES TRANSLATION.40 6.2NOTES ON THE WIESNZ08 COST WEIGHT SCHEDULE.40 6.3WIESNZ08, FOR USE WITH AR-DRG 5.0 AS ADAPTED FOR NEW ZEALAND.41 7APP

15、ENDIX 2: SAS CODE TO CALCULATE WIESNZ08 AND ASSIGN PU.80 8APPENDIX 3: CASEMIX COST WEIGHTS PROJECT GROUP MEMBERSHIP .100 9APPENDIX 4: NEW ZEALAND CASEMIX HISTORY.101 4Version 14 1Purpose of this document This document provides the definitions for inclusion of hospital events in casemix funding toget

16、her with information related to the calculation of cost weights for these events and the assignment of events to purchase units. WIESNZ08 uses the same AR-DRG set as the WIES11C framework, but new cost weights are provided. This document is the latest in a succession of annual updates that describe

17、New Zealands casemix funding environment. The documents from earlier years can be viewed on the NZHIS website: t.nz. The membership of the project group during the development of this document is given in Appendix 3. Appendix 4 contains a history of the New Zealand casemix environment s

18、ince 1998/99. 2Changes effected in this version This version includes the following major changes: a new cost weight table, based on New Zealand costs; The framework rules now indicate the appropriate non casemix purchase unit (XPU) to apply to casemix-excluded events; A more detailed list of change

19、s arising during this most recent review is given in 3.2.1. 3Introduction This report specifies the final version of the 08/09 FY1 WIESNZ08 methodology for casemix purchasing to be used by DHBs. It is the same format as the document used in earlier years, and as with the framework in 05/06, 06/07 an

20、d 07/08, WIESNZ08 is based on the DRG schedule AR-DRG v5.0 and clinical coding in ICD-10-AM 3rd Edition. The intent of this document is to specify the casemix methodology used by DHBs so that case weighted discharge values can be calculated for all National Minimum Data Set (NMDS) events by NZHIS. F

21、urther variables are also defined, as required, to identify casemix purchased Purchase Units (PUs), sometimes also referred to as Service Units, case complexity (for future costing work), and the cost weight version used. Publicly funded events excluded from casemix purchasing are identified and the

22、 correct non casemix PU applicable to the event is defined, allowing these events to be combined with the national non-admitted patient data collection (NNPaC). A secondary purpose of this document is to provide a definitive explanation of the DHB casemix purchasing framework for use throughout the

23、health sector. As such, additional information beyond that required by NZHIS for implementation on the NMDS is provided both as a background and to identify areas that may be subject to revision for future funding arrangements. 1 Financial Years run from 1 July through to 30 June of the following ca

24、lendar year and are abbreviated by stringing together the last two digits of the portions of calendar years in question, i.e. 00/01, 01/02, and 02/03 represent the 3 consecutive financial years from 1 July 2000 through 30 June 2003. 5Version 14 This specification is described as much as possible in

25、plain English. There are, however, references to lists of International Classifications of Diseases (ICD-10-AM 3rd Edition), Diagnostic Related Groupings (DRGs2) and other lists of coded variables from the data dictionary for the NMDS. Such lists, including logical conjunctions of different sets of

26、variables, are provided to exactly identify what is included (or excluded) in the English definition. The NMDS cost weight file (.ndw file) is distributed by NZHIS for each file loaded into the NMDS. The file contains the results of the WIES calculation process for each record within the file that i

27、s successfully loaded. It gives the cost weight, purchase unit and DRG for each event and a subset of information from the record that was used to calculate each of these. The file comprises a header record containing file information, and a cost weight transaction record for each record loaded to N

28、MDS. Note that the terms Hospital and Health Service (HHS) and DHB provider arm may be used interchangeably throughout this document. 3.1Background DHBs are responsible for funding their provider arms from their MoH funding packages, using the form of a service level agreement and price volume sched

29、ule agreed between a DHB and its provider arm. DHB purchasing intentions, including volume targets, are notified to the MoH in district annual plans. DHBs purchase a range of inpatient events from their provider arms, some of which are funded using this casemix framework, principally Medical/Surgica

30、l events. This document extends the existing casemix and cost weight methodology, known as Weighted Inlier Equivalent Separations (WIES), with Amendments for New Zealand from Version 11C to Version WIESNZ. The version for implementation from 1 July 2008 is known as WIESNZ08. The casemix purchase uni

31、ts appearing in this schedule are those used in DHB price volume schedules and are derived from a mapping of Health Service Speciality codes as set out in this document. See 5.3. 3.2Recent History of Changes to this Casemix Framework 3.2.1 Changes from WIES11C to WIESNZ08 The model for producing the

32、 cost weights is the WIES method, but now all data elements are from New Zealand. In particular, only New Zealand cost data has been used. These weights are for use with AR-DRG 5.0 as adapted for use in New Zealand (see footnote 2). 2 Two slightly different DRG versions are in use within the methodo

33、logy. The DRG version currently in use within the NZ health sector is AR-DRG version 5.0 and all DRG tests on NMDS events refer to this version. However, for the purposes of applying costweights, some AR-DRGs are not clinically homogeneous and in these cases an AR-DRG may be reallocated to a differe

34、nt WIES or NZ DRG referred to in this document as NZdrg50. The NZdrg50 DRGs contain all the AR-DRGs as well as four additional DRG codes (not used in AR-DRG) for the purpose of applying the appropriate costweights to NMDS events. 6Version 14 WIESNZ08 includes the following changes from WIES11C oMapp

35、ing of Carotid Stent cases to a dedicated DRG B04M. See 4.2.3; oSplit of D06Z (Sinus, Mastoid and Complex Middle Ear Procedures) into D06A (Mastoid Procedures) and D06B (Other Sinus and Complex Middle Ear Procedures). See 4.2.4; oSplit of K04Z (Major Procedures for Obesity) into K04A (Major Procedur

36、es for Obesity w/o Laparoscopy) and K04B (Major Procedures for Obesity w Laparoscopy). See 4.2.5; oA new cost weight schedule is appended in 6.3 derived from cost data supplied by New Zealand public hospitals. There are 19 new Same Day DRGs. oThe casemix exclusion rules have been extended to identif

37、y the non-casemix purchase units that apply; oTwo new agencies have been added to the list of valid agencies, however they are both excluded from casemix-funded wash-ups. oNew facilities have been added to the casemix-funded facility table. oSome existing Pregnancy and Childbirth Health Specialty Co

38、des have been retired and new ones introduced to identify events with an independent (non DHB) Lead Maternity Carer (LMC) separately from those with a DHB employed LMC. See below 3.2.2; oA new Health Specialty Code, D55, has been added to aid the identification of patients convalescing in facilities

39、 different from where their main rehabilitation will occur, usually for non-weight bearing and other interim rehabilitation stays. See below 3.2.2; oThe neonatal inclusion rule now includes only events discharged from a secondary or tertiary maternity facility. See 5.2.12; oSimultaneous transplants

40、of the kidney and pancreas were included in the cost weight development and no longer need to access the High Cost Treatment Pool. See 3.3.3. 3.2.2 New Health Specialty Codes The five new Health Specialty Codes referred to in 3.2.1 are being introduced with effect from 1 July 2008. The new codes are

41、: P60, Maternity Services Mother no Community LMC P61, Maternity Services Well Newborn no Community LMC P70, Maternity Services Mother with Community LMC P71, Maternity Services Well Newborn with Community LMC D55, Non-weight Bearing and other related Convalescence. 3.2.3 Changes from WIES11B to WIE

42、S11C WIES11C includes the following five changes from WIES11B: oThe AAA copayment has been increased to 5.4077 costweights to better reflect the costs of the stents used; oMore facilities have been added to the list of those eligible for casemix purchases. These are all private surgical hospitals wh

43、ich are subcontracted by DHB provider arms, generally to perform elective inpatient procedures to clear booking lists. They have been 7Version 14 included so that DHB provider arms that subcontract to them will have the events included in casemix; oCorrection of an oversight by adding Gisborne hospi

44、tal to the list of facilities that are eligible for maternity casemix; oTwo health specialty codes have been retired and replaced with four new ones and oThe purchaser codes list has been trimmed to reflect current purchasing sources and two new codes have been added (34 and 35). 3.2.4 Changes from

45、WIES11A to WIES11B WIES11B included two changes from WIES11A oa new purchase unit and clarification for cases eligible for the AAA and ASD co-payment. oThe new purchase unit S05.01 Anaesthesiology inpatient services. Since this purchase unit is only used at Waikato DHB, only discharges from there wi

46、ll be allocated to this new service unit. 3.2.5 The Casemix Funding Framework in 2008/09 In 2008/09 the NZHIS will introduce clinical coding in ICD-10-AM 6th Edition. Events coded in this edition will have their codes back-mapped to ICD-10-AM 3rd Edition and from there will be grouped into AR-DRG 5.

47、0. The cost weights and framework that follows in this document will then be applied. Note that costs for scoliosis implants and spinal cord stimulators were removed from the cost weights as these cases cannot be consistently identified from a definition based on procedure and diagnosis codes. Servi

48、ce DHBs may continue to invoice Domicile DHBs for these costs. This document continues the framework developed since 1998, but updates the documentation for the changes listed above. The intent of the Casemix Cost Weights project group in making the changes where rules are specified in terms of clin

49、ical code sets has been to preserve the current intent of the exclusion rules, including maternity cases. 3.3Areas for change in the future The current cost weight schedule is now based solely on New Zealand cost and other data elements. WIESNZ08 contains cost weights for the new Maternity purchase

50、framework which will become effective from 1 July 2009. There is work still to be done in relation to delivery events to allow for differing employment arrangements for midwives. See also 3.3.1. Similarly, NMDS has expanded its range of event end type codes so as to identify ED discharges and this m

51、ay be used in future cost weight studies. The advent of a new mechanism for funding, and budget management of, Pharmaceutical Cancer Treatment (PCT) drug costs means that future cost weight studies will need to be able to remove these costs before developing 8Version 14 new cost weights. Funding of

52、this component of cancer treatment is now accessed from other sources. 3.3.1 Maternity/Obstetrics Purchasing This framework contains the casemix framework for that service which will be effective for data collection and reporting (but not funding) from 1 July 2008. This set of exclusion rules for th

53、e casemix Maternity framework was introduced for the 2003/04 year, and has been reviewed for funding to start for the first time in 2009/10. Note that this new framework is the official PU framework in NNPaC effective from 1 July 2008. It may need some further review for effectiveness in conjunction

54、 with the expected future devolution of primary maternity services to DHBs. Note that in the body of this document the term Pregnancy and Childbirth may be used instead of Maternity/Obstetric. 3.3.2 Facilities used in DHB subcontracting To be valid for casemix funding an event must have both a valid

55、 agency and a valid facility recorded. Agencies valid for non casemix funding are the same as those valid for casemix funding, however some facilities are valid for non casemix funding only and these do not appear on the casemix valid facility list in 5.2.39. The advent of significant elective surge

56、ry initiatives has highlighted the need to develop a more timely procedure for adding facilities subcontracted by DHB provider arms to this framework. It is expected that NZHIS and the NPP Casemix Project group will explore ways of facilitating this. The current process has been dependent on DHBs ad

57、vising either NZHIS or the Casemix Project Group on an annual basis of any changes to the list of facilities they may use during a financial year. The eligible facility list (see 5.2.39) has been updated based on a survey of DHB provider arm electives subcontracting intentions in November 2007. 3.3.

58、3 Simultaneous transplants of the kidney and pancreas Costs for these events were accounted for in developing WIESNZ08, and so the inpatient component of these cases are now funded completely through the casemix schedule. See 5.2.19. 3.3.4 Scoliosis Spinal Implants and Spinal Cord Stimulators Note t

59、hat costs for scoliosis implants and spinal cord stimulators were removed from the cost weights as these cases cannot be consistently identified from a definition based on procedure and diagnosis codes. There is ongoing work to determine a consistent method for identifying these cases from reported

60、data elements, and to identify all service aspects of spinal cord stimulators. 3.3.5 Cancelled procedures This version does not change the casemix exclusion rule for cancelled procedures. No change was made because it is difficult to identify the reason why it was cancelled (due to the coding standa