HERC - Data - Non-VA Data

Non-VA Data

VA researchers often need data for veterans who received non-VA medical care. A common example is a cost-effectiveness analysis, which requires information on the costs of all healthcare utilization, including care obtained from non-VA providers.

There are three general methods for estimating these costs:

non-VA databases,
VA databases on contract care, and
patient self-reports

Each of these methods is discussed below. One caveat, however, is that the analyst should take care not to double-count non-VA care reported in different sources.

Non-VA databases

When veterans use non-VA health services, much of this can be obtained from existing databases. Sources of data include Medicare and Medicaid utilization data, and state discharge datasets for certain states. Most easily available are public release files, which do not include patient identifiers. A good example is HCUPnet, which provides statistics from the Healthcare Cost and Utilization Project.

In most cases, public use files do not provide sufficient information. In these cases, the research may have to apply for encrypted data or data with patient identifiers. In both cases, agencies that control encrypted or identifiable data have established a rigorous process to protect patient confidentiality. For example, to obtain encrypted or unencrypted patient identifiers associated with Medicare utilization data, the analyst must seek permission from the healthcare Centers for Medicare and Medicaid services (CMS). CMS must receive a signed data user agreement, and approve the research protocol.

The VA Information Resource Center (VIREC) has Medicare data for eligible veterans. Please contact VIREC for further details.

Non-VA Files

Among the non-VA files available to researchers are Medicare Cost Reports, American Hospital Association Survey, ZIP Code Files, and state hospital discharge reports. Some older data are on Austin. For more recent data, please contact CMS or AHA.

Medicare Cost Report
- (flat file - requires documentation)
- PRTPRD.S518DH1.PPSxx (xx identifies the year of data)

DRG Weights
- (SAS file)
- RMTPRD.S518DH1.DRGWT97

Wage Index
- (SAS file)
- RMTPRD.S518DH1.WINDEX.ALL8

American Hospital Association Survey
- (large flat file - requires documentation)
- RMTPRD.S518DLP.SURVEY.AHA97
- RMTPRD.S518DLP.AHA97.LAYOUT

ZIP Code Files
- (flat file)
- RMTPRD.S518DH1.ZIP96

Care Paid for by VA

When VA patients receive care from non-VA providers, this care may be documented in the VA Fee Basis files. The Fee Basis files report the cost of care provided under contract to VA. The Fee Basis files include a set of financial files that provide information on the cost of inpatient and outpatient provided to VA-eligible patients by contract providers. The VA discharge files, the Patient Treatment Files, includes a file that reports information on non-VA stays under contract to VA. This file includes the standard fields from the PTF dataset, including the encoded patient identifier (i.e., scrambled social security number), discharge date, length of stay, and Diagnosis Related Group.

However, a couple cautionary notes are in order. First, the amount is less than the total cost of contract care reported in the VA Cost Distribution Report and the VA Financial Management System. Payments to some contract providers, such as state veterans homes and providers under VA sharing agreements, are not reported in the Fee Basis system. Second, this file is not frequently used by researchers. Therefore not all of its strengths and weaknesses are known. Caveat emptor.

Self-report

Information on non-VA services use may be obtained directly from the participant. Below are a couple things to keep in mind.

Categories of care

Self-report questions should focus on categories of care for which costs are different and for which patients cognitively keep them separate. For example, it is common to ask about nights of inpatient care and then number of outpatient visits. However, it is probably not a good idea to ask about nights of intensive care unit (ICU) hospitalizations. Patients may recall being in an ICU, but are unlikely to be able to separate these categories accurately.

Validation

If the analyst uses the VA utilization databases and uses self-report for non-VA care, it is highly recommended that one set of questions specifically pertain VA care and a second set of questions pertain to non-VA care. This permits validating the accuracy of self-reporting for the study sample.

Cost

In almost every case, patients are not reliable sources of cost information because they rarely see the bill(s); bills can be confusing to say the least, and because recall of these data is not accurate. Therefore, the analyst must multiple the self-report data (i.e., units) with estimated unit costs.

For more information on self-report, please see Bhandari, A., Wagner, T.H. (2006). "Self-reported utilization of health care services: improving measurement and accuracy." Med Care Res Rev 63(2): 217-35. Reprints can be obtained from Todd Wagner by contacting him directly or by contacting HERC.