VA Health Care Data at the Austin Automation Center Paul G. Barnett, PhD April 4, 2003

Overview of presentation Origin of data- Where do data come from? Organization of data– –What data are available? –Which file do I use? Source of documentation- Where can I learn more?

Where do the data come from? Veterans Information Systems & Technology Architecture (VISTA) National Patient Care Database (NPCD) Extracts of NPCD- SAS Files at Austin

Veterans Information Systems & Technology Architecture (VISTA) Computer system at each medical center Formerly called Decentralized Hospital Care Program (DHCP) Also called CPRS Data are periodically extracted and transmitted to Austin

National Patient Care Database (NPCD) Located at the Austin Automation center A large data base that cannot be accessed by researchers Used by Austin to generate user accessible files, the “SAS extracts”

Which file do I use? SAS Extracts of NPCD Hospital Discharge –Patient Treatment Files (PTF) Outpatient Visits –Outpatient Care Files (OPC)

PTF files Four sets of files in PTF based on type of care Each set has multiple files with different data

Sets of files Sets are mutually exclusive A given hospital stay appears in only one set of files Stays are assigned to one of the following: –NON-EXTENDED CARE –EXTENDED CARE –OBSERVATION –NON-VA

NON-EXTENDED CARE Most VA stays –Acute medical and surgical stays –Psychiatry –Rehabilitation –Excludes most extended care and observation stays Patient may be transferred, so some extended care and observation stays are in these files!

EXTENDED CARE Predominantly extended care unit stays –Patient may be transferred to other parts of hospital –thus some acute care is in these files! Includes community nursing home care –thus some non-VA care is in these files! –STATYP=42 indicates community nursing home care in this file

OBSERVATION Observation unit stays visits –Are treated as hospital stays by VISTA –Are not considered hospital stays for VA performance measures Vast majority of files consist of observation visits of 1 day or less Patient may be transferred to other parts of hospital –Thus some acute and even extended care occasionally appear in these files!

NON-VA files Stays at non-VA hospitals under contract with VA Community nursing home stays in extended care file

Which set of files to use? Unexpected types of care may be found in files –Some extended and observation care is in non- extended file –Some acute care and non-VA care is in extended care file –Some acute care is in observation file Search all files!

CENSUS files Patients still in hospital on September 30 These stays are incomplete; when the stay is finished, it is reported in other files. Census file may be needed –if analyst wants to know about stays that are not yet over –for some studies of long-term care, as some stays last many years

Types of files Each hospital stay is characterized in different files A set of files is made up of the following types –MAIN –BEDSECTION –SURGERY –PROCEDURES

PTF File Names Type of care file vs. type of file Non-Extended Care Extended Care Observation MainPMXMPMO BedsectionPBXBPBO SurgeryPSXS-- ProcedurePPXP--

MAIN file One record per hospital stay Variables pertain to entire stay Characteristics of patient –Scrambled Social Security number (SCRSSN) –Age, gender, zip code of residence Characteristics of stay –Medical center number (STA3N), admission date, discharge date, diagnoses

BEDSECTION file Bedsection (BEDSECN) is 2 digit code that indicates the location of care Bedsection file has one record for each bedsection visited by patient –One to several records per hospital stay –e.g. stay that involved days in Medical Intensive Care (12) and General Acute Medicine (15) has two records in this file

BEDSECTON file (cont.) BEDSECN is actually “treating specialty”- the service of the treating physician PLBED is the location of care, but this variable does not always have a value

MAIN vs. BEDSECTION Some variables are in both Files may be merged on the variables that define a stay: –SCRSSN, ADMITDAY, ADTIME, DISDAY, STA3N, SRTKEY –Rare duplicate records distinguished only by difference in STA6A (6 digit station code)

PTF Surgery File Reports ICD-9 codes for surgical procedures Each record has up to 5 surgical procedures At least one record for every day that a surgery is performed –A second record if more than 5 surgeries in a day –Zero to several records for a hospital stay Merge with other files using stay defining variables

PTF Procedures File Like surgery file, but reports medical procedures A given ICD-9 procedure code may appear in either the surgery or procedure file— –Analyst should look in both files!

Outpatient NPCD SAS extract files Outpatient Care Files (OPC) –EVENTS –PROCEDURES –DIAGNOSIS –VISITS These different files contain overlapping information –A single outpatient visit may appear in every file!

EVENTS (SE) Comprehensive file –All outpatient visits in NPCD –Doesn’t include non-VA care –May exclude some outpatient care Characteristics of patient Characteristics of visit

Events File- characteristics of patient Scrambled Social Security No. (SCRSSN) Age (but not birth date) Gender (SEX) Eligibility category (ELIG) Zip code of residence (ZIP)

Event File- characteristics of visit Station (STA3N, STA5A) Clinic stop visited (CL) Date of visit (VIZDAY) Provider (up to 10) –Provider Type –Provider ID (can’t be decoded) ICD-9 diagnosis codes (up to 10) CPT procedure codes (up to 15)

Stop Code 3 digit code for location of care Now called “DSS identifier” Policy defines stop codes: CostData_Files/dss-identifiers_3-00.doc Primary stop code– This is what matters Secondary “credit” stop code– Should be ignored –Policy limits its use to specific modifiers –Many sites still use old rules, inappropriately

Using the SE file Job Control Language (JCL) specification –DD name may require trailing zero (0) “most recent file” –E.g., for FY00: //IN1 DD DSN=MDPPRD.MDP.SAS.SE00(0),DISP=SHR

Using the SE file- example Trailing zero used in DD statement but not in SAS statement //S640XXX6 JOB TSO01C19,S640PGB, // NOTIFY=&SYSUID,MSGCLASS=I //STEP1 EXEC SAS,REGION=5000K,SOUT=R,WORK='500,100' //IN1 DD DSN=MDPPRD.MDP.SAS.SE00(0),DISP=SHR //LIBRARY DD DSN=MDPPRD.MDP.FMTLIB6,DISP=SHR //SYSIN DD * OPTIONS NOCENTER LS=78 PS=266 ; PROC MEANS DATA=IN1.SE00 N MEAN MIN MAX SUM;

PROCEDURES (SC) Has CPT procedure codes –Up to 12 procedure codes reported –Compared to 15 codes in events (SE) file Was discontinued in FY2002

DIAGNOSIS (SG) Has ICD-9 diagnosis codes Limited to visits in which a diagnosis was assigned Was discontinued in FY2002

VISITS (SF) Has demographics, list of up to 15 stops visited on a single day by that patient No diagnosis or procedure Visits prior to 1997 have secondary stop code– not comparable to visits file for subsequent years

Regional outpatient files Some files are divided into segments by geographic region Use regional files if your analysis is limited to a single region, as jobs will run much more quickly

Unscrambling Social Security Numbers (SSNs) Each true SSN has exactly one scrambled SSN Special permission is required to unscramble (or scramble) –Approval at national level –Research use requires IRB approval –With approval, Information Security Officer adds special “Functional Task Codes” to your Austin profile For each data base, a file links true and scrambled SSNs

Information on NPCD SAS extracts –Manuals on PTF and OPC available from VA Information Resource Center (VIREC) – FY2000 version just released Tabulation of key variables

Other important at Austin files Long-term care files –Patient Assessment File indicates patient severity –Replaced by Minimum Data Set (MDS) –See long-term care guidebooks

Financial Files at Austin (text files) Financial Management System (FMS) –Cost by service (e.g. nursing, medicine) Cost Distribution Report (CDR) –Cost by patient care department (e.g., inpatient surgery, psychiatry)

VA Fee Basis Files Information on care provided to veterans by providers under contract to VA Fee basis files: –Acute hospital stays –Ancillary services provided to inpatients –Outpatient services –Payments to pharmacies –Travel expenses

Decision Support System Combines clinical and financial data from VISTA Cost of: –VA health care products –VA health care stays and visits Clinical data including –Results of 49 lab tests

Where do DSS data come from? VISTA Workload and patient data DSS VISN Level Production Databases (at Austin but limited access) Extracts of DSS- SAS Files at Austin Time allocation Relative costs

DSS national extracts Cost files Clinical files

DSS national cost extracts--Inpatient cost files Discharge- One record per hospital stay –(like PTF main files) Treating specialty- One record for each month in a bed section, includes census patients –(like PTF bed section files, but one record per month, and includes census) These files overlap

DSS national cost extracts--Outpatient cost files Outpatient visits –Designed to have records not in SE file –Some visits in SE file not present in FY2000 extract Pharmacy These files are mutually exclusive

DSS national cost extracts First created in 1998 FY2000 data may be reliable at some sites User must beware!

DSS Department cost file (ALBCC) Cost of each Account Level Budget Cost Center at each medical center

DSS clinical extracts Laboratory tests done (inpatient and outpatient) Laboratory results (49 tests) Planned extracts: –Pharmacy –Radiology

Other VA files at Austin BIRLS –Gives dates death for veterans Compensation and Pension files –Identifies veterans with service connected disabilities Enrollment files

Other files at Austin Medicare Reports –Medicare Cost Reports –HCFA DRG Weights –HCFA Wage Index American Hospital Association Survey Area Resource File ZIP Code Files State hospital discharge reports

Where can I learn more? VA Information Resource Center – –(708) (Central Time) Health Economics Resource Center – –(650) (Pacific Time)

VIREC vs. HERC VIREC: Questions about clinical and utilization files; –PTF, OPC, long-term care files, DSS clinical data HERC: Questions about financial datasets –FMS, CDR, DSS cost data

HSRData group discussion group of VA data users See VIREC web site on how to join