Access
Access to VistA data is limited to VA employees whose work requires their
use and to VA and other researchers who have obtained authorization from
the local Institutional Review Board (IRB) and the local Information Resources
Management Office (IRM). Once the IRB has approved the use of patient-level
data, the IRM can be approached regarding technical arrangements for becoming
an authorized user of the local information system. IRM can provide the name
of the ADPAC (local Automatic Data Processing Application Coordinator) who should
be your point of contact with IRM. For IRM contact information, see the VA's Facility Directory.
Extracting VistA Data For
Research
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Researchers must be working on a project approved by the local Institutional
Review Board (IRB) for access to patient-identifiable data to be allowed
access to VistA data.
Since VistA includes no analytic software, data to be analyzed must first
be extracted from VistA and transferred to a different platform. VistA provides
several avenues to access and extract data. New Care Management software
includes a query tool for sorting and exporting data for multiple patients
simultaneously. The VA FileMan, Health Summary, and Patient Data Exchange
(PDX) VistA utilities all provide access to patient data. Some sites have
an SQL interface available for direct SQL access to Vista data files . A
programmer connected with an IRM department or with a VA research Center
of Excellence could provide customized extraction programs if funding
can be arranged. Which method is best will depend on the number of records
to be requested, the complexity of the data extraction request, the number
of sites to be included and the availability of programming support.
Even if you plan to employ a programmer to extract data, knowledge of the
contents and formats of the VistA source files and of methods of extraction
is beneficial. IRM often maintains a "mirror" system for training and testing
software changes. With access to that "mirror" system you can familiarize
yourself with how VistA operates. Familiarity with VistA source files can
help with formulating requests to the programmer, with interpreting extracted
data and with checking data for accuracy, consistency, duplicates, and missing
data. An informed estimate of the complexity of the programmer's task makes
it possible to anticipate programming time and costs and the impact of the
job on the operation of medical center's VistA system.
To enable your PC to access VistA, contact the Automatic Data Processing
(ADP) Coordinator for your service. Each division within a VA facility is
assigned an ADP Coordinator who acts as liaison between that service and
IRM. IRM offices acquire and maintain the hardware and software of VistA.
IRM will provide authorization codes and establish access to software to
make data extraction possible, but the request for VistA access must be placed
through your ADP Coordinator.
Departments that are responsible for entering data into any part of VistA
have Automatic Data Processing Application Coordinators, called ADPACs, who
are authorities on the local installation of software packages employed by
their departments. ADPACs often have an understanding of the format and contents
of data files and insights into the meaning and utility of the data that
are extremely useful to research. ADPACs can also advise on the parameters
to be requested from IRM for your PC to facilitate successful access to the
desired data.
VA FileMan is the database management program used to access and manage
VistA data. VA FileMan user manuals, both beginner's and advanced, are available
online at the VistA Documentation
Library.
VA FileMan's List File Attributes (DILIST) option can provide a data dictionary,
that is, a list of the fields in a data file and their characteristics. Using
VA FileMan's Print File Entries (DIPRINT) option, data can be retrieved from
VistA for export to another platform. To display all or a subset of data
elements within a single file, for a single record or for a small number
of records, use the Inquire to File Entries (DIINQUIRE) option. DILIST, DIPRINT
and DIINQUIRE are just three of many options on the VA FileMan menu and all
three are very useful for better understanding the data files to be included
in your analysis.
When IRM sets up your FileMan access, they select the VA FileMan menu options
that will be available to you. A request for DILIST, DIPRINT AND DIINQUIRE
can be placed through your ADPAC.
For each data file you intend to access, you must request access through
your ADPAC, so that IRM can assign you the appropriate security code. The VistA
Documentation Library is a good place to begin identifying data files
needed for an analysis. Application user manuals available there generally
show the names of data files created by that application. Because VistA distributes
data for one patient encounter to numerous files created by several applications,
investigators often require data from several files. The local ADPAC for
the primary medical service of interest can offer insight regarding what
data files will need to be consulted.
VA FileMan cannot be used to access data files remotely so its utility for
multi-site studies is limited. Furthermore, VA FileMan can only operate on
data files you are authorized to access. Permission for "Read Access" will
need to be obtained from the ADPAC for each of the services whose data you
use.
Using VA FileMan to navigate through multiple encounter-specific VistA files
to access patient information can quickly become a very complex process.
Data requests may become too intricate for a new FileMan user to create or
the execution may require so much computer time that the medical facility
information system is adversely affected. Complex data requests that could
cripple the system if done through FileMan can often be accomplished far
more efficiently using MUMPS ( Massachusetts General Hospital Utility Multi-Programming
System), the primary programming language of the VistA environment.
Care Management Query Tool
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Care Management software provides a query tool that makes data for multiple
patients sortable and exportable directly from VistA. T he query tool can
identify a cohort of patients, based on filters such as a membership in a
local disease registry, primary care provider, abnormal test results, an
appointment in a specific clinic or within a date range, orders placed, inpatient
and ward lists, etc. Along with patient name, age, social security number
(last four digits only) and ward location, these fields can be exported to
a tab delimited text file for analysis on another platform.
Not all clinical data are available through Care Management. Designed to
prevent important information from being overlooked, Care Management searches
in the Orders File, the Visit/Appointment file and the Text Integration Utilities
(TIU) document file (e.g., progress notes, consults, procedures, etc.) and
displays critical elements such as consult status, test results, significant
findings, and events such as admissions, transfers, discharges, and outpatient
visits. Data elements that may be displayed in a query report are listed
below.
VistA Data Elements Displayable in Query Reports
Patient Information |
Documents |
Name
SSN (last four digits only)
Age
Ward Location
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Reference Date/Time
Title
Author
Status
Expected Cosigner
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Orders and Consults |
Visits/Appointments |
Order Date/Time
Ordering Provider
Order Text
Order Status
Signature Status
Result Flag (abnormal, critical, significant)
Significant Finding
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Date/Time
Location
Visit Status
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Screen-by-screen instructions for using the query tool are available online
in the CPRS
QUERY USER MANUAL .
CPRS access through your PC should be arranged with IRM through your ADPAC,
with a request to be assigned the menu item "ORRCM REPORTING" which
allows use of the query tool. Access to local disease registries, if included
in your IRB permission, should be confirmed with IRM as well.
Health Summary/Patient
Data Exchange
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A Health Summary is
a report that presents information gleaned from various VistA applications
for an individual patient or group of patients. Some nationally available,
standard Health Summaries focus on topics such as allergies, clinical procedures,
active medical problems, current orders, demographics, discharge summary,
future appointments , initial assessment, perioperative assessment , reminders
due , surgery reports, selected laboratory results or detailed vitals. New
Health Summaries can be custom designed by users, either by amending an available
Health Summary or entirely from scratch.
Any of these VistA applications can provide data elements for a Health Summary:
Outpatient Pharmacy
Allergy Tracking System
Clinical Reminders
Consults
Dietetics
Discharge Summary
Inpatient Medications
Lab
Medicine
Mental Health
Nursing (Vital Signs)
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Order Entry/Results Reporting
Patient Care Encounter
Problem List
Progress Notes
Radiology
Registration
Scheduling
Social Work
Surgery
VISTA Imaging
Automated Medical Information Exchange |
Remote patient data can be viewed through CPRS if the local and remote sites
have an identically named Health Summary type, (and if both IRMs have all
the necessary patches installed). For non-nationally released health summary
reports, however, the report may vary from site to site. Reports will appear
in the structure and configuration defined at the remote site.
Health Summaries can also be transmitted between facilities using Patient
Data Exchange (PDX) software and the MailMan electronic mail utility. The
PDX menu will allow you to request patient reports from other facilities,
but requests must be made one patient at a time. Responses may need to be
manually produced at the remote site, for which time must be allowed.
VistA's Health Summary software produces a report, not a data file. Data
for a very small cohort can be manually transferred from a report to a data
file for analysis. For larger cohorts, software is available that can build
a data file from elements extracted from electronic reports.
In general, Health Summaries and PDX are best for small extractions, for
example, for following a small cohort of previously selected patients at
a few sites, or for repeated access, for example, to retrieve clinical test
results. Health Summaries automatically include data from many different
confidential files, as contrasted with VA FileMan, for which permission must
be granted for the use of each data file and which provides no remote access.
Health Summary information must be requested patient by patient, though,
and time limits and max occurrences (number of patients or number of readings,
e.g., for vitals) apply.
If you plan to customize the standard medical center reports or to create
your own report, alert your ADPAC that you will need Health Summary's Enhanced
User Menu. If you plan to request data from a remote location, request PDX
and spooler settings that will allow you to send and receive data files.
SQL
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Investigators planning to construct a relational database of VistA data
will find that few sites offer direct access to VistA data using SQL (Structured
Query Language). Instead, data are most often exported from VistA with an
M or MUMPS ( Massachusetts General Hospital Utility Multi-Programming System)
program and then mapped to a relational database .
Commercially available software applications like MUMPS Data Extractor (MDE)
and KB SQL allow direct SQL access to MUMPS data. Another M-based SQL mapping
system is built into VistA's Cache. A few sites have the necessary software
for direct M-to-SQL access but several more tried and abandoned it. They
found it was too expensive and/or put too much strain on the operation of
the local VistA system.
The VA FileMan application SQL Interface (SQLI) was an attempt to provide
the data dictionary information needed to map VA FileMan files to a relational
database. SQLI is not able to provide access to VA FileMan data on its own.
Instead, it provides information about VA FileMan's internal data dictionary
to an M-to-SQL application like KB SQL or MDE. Since the available M-to-SQL
products can map VA FileMan data without help from SQLI, SQLI has not been
heavily used.
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