RESEARCHERS’ GUIDE TO VA DATA

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2013-2014 VIReC Database and Methods Cyber Seminar Series 

Measuring Veterans Health Services 

Use in VA and Medicare

January 6, 2014

 Presented by:

Kristin de Groot, MPH
Topics for Today

Overview of Medicare Claims

Medicare Claims Data

Identifying Health Care Use in 

Medicare Claims

Common Measures and Research 

Examples

Data Access and Assistance RESEARCHERS’ GUIDE TO VA DATA

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RESEARCHERS’ GUIDE TO VA DATA

Audience Poll

(Heidi convert to poll function)

Have you ever used any of the Medicare 

claims datasets?

– Yes 

– No

How would you rate your overall knowledge 

of the Medicare claims datasets?

– 1 (No knowledge)

– 2 

– 3 

– 4 

– 5 (Expert-level knowledge)

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RESEARCHERS’ GUIDE TO VA DATA

Overview of Medicare Claims

Medicare Claims Data

Identifying Health Care Use in 

Medicare Claims

Common Measures and Research 

Examples

Data Access and Assistance

Topics for Today

4 
RESEARCHERS’ GUIDE TO VA DATA

Why are Medicare Data important?

Many Veterans who use VA health care 

also obtain care outside VA

Researchers need full picture of health 

care use to draw accurate conclusions

Almost all Veterans age 65 and older are 

enrolled in Medicare

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RESEARCHERS’ GUIDE TO VA DATA

VA and Medicare Billing

The VA does NOT bill 

Medicare for services 

provided at a VA 

facility. 

In most situations, 

Medicare providers 

can NOT bill the VA for 

services provided

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VA Medical Center Community Hospital

VA pays Medicare pays

BILLS
RESEARCHERS’ GUIDE TO VA DATA

How the data get from 

“Bedside to Bench”

A Medicare beneficiary obtains 

healthcare outside the VHA

The provider submits claims (i.e. bills) 

to the Centers for Medicare and 

Medicaid Services (CMS) for 

reimbursement

Claims are collected by CMS, stored in 

databases, and released to researchers 

as analytic datasets

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RESEARCHERS’ GUIDE TO VA DATA

Strengths of Medicare Claims Data

Data directly related to billing is likely to 

be accurate

– SSN (or scrambled SSN)

– Charge and payment amounts 

– Dates 

– Diagnosis codes

– Procedure codes

– Provider information

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RESEARCHERS’ GUIDE TO VA DATA

Limitations of Medicare Claims Data

No/Limited data on:

– Data not needed for billing

• Demographics (Marital Status, Education, 

Income)

• Clinical Data (Lab Results, Vital Signs, 

Symptoms)

– Services not billed (non-covered services)

– Managed care (HMO) enrollees

Care-to-claim relationship can be 

complicated

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RESEARCHERS’ GUIDE TO VA DATA

One Event, Multiple Claims

Long stays may not be contained in one 

claim 

Events may have 2 types of claims

– Facility charges 

– Physician charges 

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Stay Claim

Admit: December 15

Discharge: January 15

Claim 1 From: Dec 15

Thru: Dec 31

Claim 2 From: January 1

Thru: January 15
RESEARCHERS’ GUIDE TO VA DATA

Multiple Events, One Claim

Many Medicare services are paid using 

Prospective Payment System (PPS)

– Single payment is made to cover all services

– Providers often not required to itemize all 

services provided

– Levels of detail vary

– PPS used is based on provider type

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RESEARCHERS’ GUIDE TO VA DATA

PPS Examples

Hospice

– Per diem rate based on category of care

Skilled Nursing Facility

– Per diem rate based on patient’s Resource 

Utilization Group (RUG)

Acute Inpatient

– Based on patient’s Diagnostic Related Group 

(DRG)

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RESEARCHERS’ GUIDE TO VA DATA

Overview of Medicare Claims

Medicare Claims Data

Identifying Health Care Use in 

Medicare Claims

Common Measures and Research 

Examples

Data Access and Assistance

Topics for Today

13
RESEARCHERS’ GUIDE TO VA DATA

Bills & Providers

Two types of bills are used to submit claims

Type of bill used is determined by type of 

provider

Types of 

Providers Examples Bill Medicare Coverage

Institutional

Hospitals

Skilled Nursing Facilities

Home Health Agencies

Hospices

CMS 1450/

UB-04

Part A or Part B

NoninstitutionalPhysicians, Clinical Labs, 

Ambulance, Suppliers CMS 1500 Part B
Medicare Claims Files

Institutional Files

– Inpatient 

– Skilled Nursing Facility (SNF)

– Hospice

– Home Health Agency (HHA)

– Outpatient

Institutional Stay Level File

– Medicare Provider Analysis and Review 

(MedPAR)

Non-institutional Files

– Carrier (Physician/Supplier)

– Durable Medical ERE

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RESEARCHERS’ GUIDE TO VA DATA

Inpatient File

Includes services provided by short and 

long-term hospitals

– 90% short-term (acute) hospitals

– Rehab, psych, other long-term hospitals

Includes facility charges

A stay may involve one or multiple claims

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RESEARCHERS’ GUIDE TO VA DATA

Skilled Nursing Facility File

Includes services provided by a skilled 

nursing facility 

– Skilled nursing and rehabilitation care 

– Does not include custodial care

Includes facility charges

A stay often involves multiple claims

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RESEARCHERS’ GUIDE TO VA DATA

MedPAR File

Created from Inpatient and Skilled 

Nursing Facility (SNF) claims

Claims are “rolled up” to the stay level

– Eliminates need for researchers to do this 

manually

Contains many summary variables

Does not contain all variables from 

Inpatient/SNF files

Only diagnosis and procedures codes 

from last Inpatient/SNF claim

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RESEARCHERS’ GUIDE TO VA DATA

Hospice File

Includes services provided when doctor 

has certified life expectancy of 6 months 

or less

– Care at home (80-90%) or as inpatient

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RESEARCHERS’ GUIDE TO VA DATA

Home Health Agency File

Includes services provided by Medicarecertified home health agencies:

– Skilled nursing

– Physical/occupational/speech therapy

– Home health aide

Up to 60 days of care on one claim

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RESEARCHERS’ GUIDE TO VA DATA

Outpatient File

Includes services provided by 

institutional facilities (mostly hospitals)

– Laboratory 

– Radiology 

– Physical therapy

– Dialysis

– Emergency room 

Includes facility charges

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RESEARCHERS’ GUIDE TO VA DATA

Carrier File

Previously known as Physician/Supplier 

File

Includes:

– Physician services

• Outpatient setting: Office visits, procedures

• Inpatient settings: Consultations, services in 

hospitals & nursing facilities

• Emergency room

– Ambulance providers 

– Clinical laboratories

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RESEARCHERS’ GUIDE TO VA DATA

Durable Medical Equipment File

Includes:

– Wheelchairs and hospital beds

• Rental or purchase 

– Prosthetics and orthotics

– Oxygen 

– Diabetic testing supplies

– Drugs (limited coverage) provided in outpatient 

setting

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RESEARCHERS’ GUIDE TO VA DATA

Part D Data

About a third of VHA/Medicare enrolled 

Veterans are enrolled Part D

Different than Medicare Parts A & B

– Claims for drugs are paid for by insurance 

companies, not CMS

– Insurance companies submit data to CMS on all 

prescription fills

Data for research use

– Prescription Drug Event (PDE)

– Drug, Pharmacy, Prescriber, Plan Characteristics 

– Slim File is subset of PDE data

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RESEARCHERS’ GUIDE TO VA DATA

Overview of Medicare Claims

Medicare Claims Data

Identifying Health Care Use in 

Medicare Claims

Common Measures and Research 

Examples

Data Access and Assistance

Topics for Today

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RESEARCHERS’ GUIDE TO VA DATA

Identifying Inpatient/SN Services

Inpatient/Skilled Nursing care are 

provided by institutional providers

– And often non-institutional providers too

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Types of Providers Examples Dataset

Institutional Hospitals/SNF Inpatient/SNF or 

MedPAR files

Non-institutional Physicians Carrier file
RESEARCHERS’ GUIDE TO VA DATA

What File(s) Should I use when Studying 

Inpatient/SNF Stays?

Choose MedPAR 

when studying: 

– Number of stays 

– Length of stay 

– Total cost

Choose Inpatient 

or SNF when 

studying:

– Detailed charges

– All diagnosis & 

procedure codes

Add Carrier when 

studying:

– Consults

– All procedures

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RESEARCHERS’ GUIDE TO VA DATA

Identifying Outpatient Services

Outpatient services may be provided by 

both institutional and non-institutional 

providers

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Types of Providers Examples Dataset

Institutional Hospitals Outpatient File

Non-institutional Physicians Carrier File
RESEARCHERS’ GUIDE TO VA DATA

What File(s) Should I use when Studying 

Outpatient Events?

In most cases, use both Outpatient and 

Carrier

Some events will have claims in both files

– Emergency room

Add HHA when studying services that 

could be provided at home

– Physical/occupational/speech therapy

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RESEARCHERS’ GUIDE TO VA DATA

Overview of Medicare Claims

Medicare Claims Data

Identifying Health Care Use in 

Medicare Claims

Common Measures and Research 

Examples

Data Access and Assistance

Topics for Today

30
RESEARCHERS’ GUIDE TO VA DATA

Measures Using Medicare Claims

Four common ways of measuring 

healthcare use using Medicare data:

1. Procedures

2. Costs

3. Inpatient Stays 

4. Outpatient Visits

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RESEARCHERS’ GUIDE TO VA DATA

Measures: Examples from Four Research 

Studies 

Procedures: 

– Walter L, et al. Impact of age and comorbidity on colorectal 

cancer screening among older veterans. Ann Intern Med. 2009 

April 7;150(7):465-473.

Cost: 

– Hubbard Winkler S, et al. Cost, Utilization, and Policy of 

Provision of Assistive Technology Devices to Veterans 

Poststroke by Medicare and VA. Med Care. 2010;48:558-562.

Inpatient Stays: 

– Weeks W, et al. Do older rural and urban veterans experience 

different rates of unplanned readmission to VA and non-VA 

hospitals? J Rural Health. 2009 Winter; 25(1):62-9.

Outpatient Visits: 

– Liu C-F, et al. Reliance on Veterans Affairs outpatient care by 

Medicare-eligible veterans. Med Care. 2011 Oct;49(10):911-7.

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RESEARCHERS’ GUIDE TO VA DATA

Procedures 

Two types of procedure codes in Medicare 

claims data

– ICD-9 procedure/surgery codes

• MedPAR and Inpatient files

– Healthcare Common Procedure Coding System 

(HCPCS)

• CPT procedure codes + CMS developed codes

• CMS developed codes are alpha-numeric

• Outpatient, HHA, Carrier, DME files

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RESEARCHERS’ GUIDE TO VA DATA

Example: Using Procedures

Walter L, et al, Ann Intern Med, 2009 

Goal

– To determine whether colorectal cancer 

screening is targeted to healthy patients and is 

avoided in patients with severe comorbidity

Cohort

– VHA outpatient users at 4 VAMCs during 2000

– 70+ years old

– Due for a screening

– Not enrolled in Medicare managed care

– N= 27,068 

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RESEARCHERS’ GUIDE TO VA DATA

Example: Using Procedures

Walter L, et al, Ann Intern Med, 2009 

Methods

– Used diagnosis codes found in 2000 VA and 

Medicare inpatient and outpatient data to 

calculate Charlson-Deyo co-morbidity score

– Searched for procedure codes indicating 

colorectal cancer screening during 2001-2002

• VA outpatient data - CPT codes 

• Medicare Outpatient and Carrier files – HCPCS 

codes 

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RESEARCHERS’ GUIDE TO VA DATA

Example: Using Procedures

Walter L, et al, Ann Intern Med, 2009 

Selected Results

– Overall, 46% of patients received colorectal 

cancer screening

• 33% of screenings were in the Medicare system

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Characteristic

Adjusted Colorectal Cancer 

Screening 2-Year 

Cumulative Incidence

Age 70-74

75-79

80+

47.2%

46.3%

43.9%

Charlson

Score 

0 (best health)

1-3 

4+ (worst health)

47.0%

45.8%

40.7%
RESEARCHERS’ GUIDE TO VA DATA

Costs 

Charges submitted to Medicare

Payments made to providers by

– Medicare 

– Beneficiaries (deductibles & copayments)

– Primary payers (some insurance)

Claims do not include payments 

made by secondary payers (some 

insurance and Medigap) 

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RESEARCHERS’ GUIDE TO VA DATA

Example: Using Costs

Hubbard Winkler et al., Medical Care, 2010 

Goal

– Compare purchases of assistive technology 

devices (ATDs) in Medicare and VA

Cohort

– Veterans who were hospitalized in a VA hospital 

for stroke during FY01-02

– Age 65+ at time of stroke

– N=12,046

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RESEARCHERS’ GUIDE TO VA DATA

Example: Using Costs

Hubbard Winkler et al., Medical Care, 2010 

Methods

– 2-year study post-stroke

– Compared 6 products in VA and Medicare data

– Used HCPCS codes to identify products

– Data on ATDs obtained from:

• VA National Prosthetic Patient Database

• Medicare Durable Medical Equipment file 

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RESEARCHERS’ GUIDE TO VA DATA

Example: Using Costs

Hubbard Winkler et al., Medical Care, 2010 

Selected Results

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Device HCPCS

Median

Medicare 

Purchase 

Median

VA 

Purchase 

Walker-folding E0135 $67 $29

Walker-wheeled/folding E0143 $95 $48

Commode chair E0163 $90 $33

Wheelchairs-power K0011 $4,650 $3,421

Ankle Foot Orthotic, 

standard

L1930 $188 $35

Ankle Foot Orthotic, 

custom

L1970 $598 $599
RESEARCHERS’ GUIDE TO VA DATA

Inpatient Stays

Measure Data Elements

Days • Admission & discharge dates

• Procedure dates

Provider 

information

• Facility number

• Attending physician UPIN/NPI

Types of care 

provided 

• ICD-9 procedure/surgery codes

• Revenue center codes

• Diagnostic Related Group (DRG)

Patient condition • ICD-9 diagnosis codes

• Diagnostic Related Group (DRG)

Outcome at 

discharge 

• Discharge status/destination

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RESEARCHERS’ GUIDE TO VA DATA

Inpatient Stays: VA vs. Medicare

VA facility

– Acute care

– Rehab

1 stay

Medicare

– Acute care facility

– Rehab facility

2 stays

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RESEARCHERS’ GUIDE TO VA DATA

Example: Using Stays

Weeks W, et al., J Rural Health, 2009 

Goal:

– To determine whether rural Veterans have 

higher rates of hospital readmission than urban 

Veterans 

Cohort

– Admissions in VA hospitals OR paid by Medicare 

Fee-for-Service from 1997-2004

– Discharged to home

– Age 65+

– Living in rural or urban areas

– 2,810,067 Veterans

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RESEARCHERS’ GUIDE TO VA DATA

Example: Using Stays

Weeks W, et al., J Rural Health, 2009 

Methods

– Inpatient care obtained from

• VA Patient Treatment File (aka Inpatient Medical 

SAS datasets)

• Medicare MedPAR file

– Identified readmissions occurring within 30 days 

of being discharged

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RESEARCHERS’ GUIDE TO VA DATA

Example: Using Stays

Weeks W, et al., J Rural Health, 2009 

Selected Results

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Place 

of 

Index 

Adm.

Total Admissions Place of 

Readmission 

Readmission Rate

Rural Urban Rural Urban

VA 296,324 854,476

VA 17.2% 18.5%

Non-VA 3.5% 2.7%

Non-VA 698,126 1,664,986

Non-VA 15.4% 14.9%

VA 1.4% 1.2%

Any 994,450 2,519,462 Any 17.96% 17.86%
RESEARCHERS’ GUIDE TO VA DATA

Outpatient Visits

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Measure Data Elements

Days • Claim from and thru dates

• Expense dates (non-inst) 

• Revenue center dates (inst) 

Provider information • UPIN/NPI number

• Place of service (non-inst) 

• Facility number (inst) 

Types of care 

provided 

• HCPCS procedure codes

• BETOS code (non-inst) 

• Type of Service code (non-inst) 

• Revenue center Codes (inst) 

Patient condition • ICD-9 diagnosis codes
RESEARCHERS’ GUIDE TO VA DATA

Outpatient Visits: VA vs. Medicare

VA (same day)

– Primary care

– Specialist

– Therapy

1 visit, 3 events

1 day of care 

Medicare

– Primary care

– Specialist

– Therapy

3 visits/claims

1, 2, or 3 days 

of care 

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RESEARCHERS’ GUIDE TO VA DATA

Example: Using Visits

Liu C-F, et al. Medical Care, 2011

Goal

– Examine longitudinal changes in Medicareeligible veterans’ reliance on VA outpatient care

Cohort

– Medicare-eligible Veterans who used VA primary 

care in FY2000

– Not enrolled in Medicare managed care

– N=15,520

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RESEARCHERS’ GUIDE TO VA DATA

Example: Using Visits

Liu C-F, et al. Medical Care, 2011

Methods

– Measured co-morbidity based on diagnosis 

codes from 2000 VA and Medicare data

– Tracked outpatient utilization in VA and 

Medicare from FY2001-2004

– Developed algorithm to classify VA and 

Medicare visits

• Primary, specialty, mental health, other 

• Using provider specialty and CPT/HCPCS 

procedure codes

– Calculated proportion of primary and specialty 

care occurring in the VA

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RESEARCHERS’ GUIDE TO VA DATA

Example: Using Visits

Liu C-F, et al. Medical Care, 2011

Selected Results

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FY01 FY04

Primary Care Visits

VA 2.4 1.9

Medicare 1.3 1.6

Total 3.7 3.3

Specialty Care Visits

VA 4.1 3.7

Medicare 3.7 8.8

Total 10.8 12.4

Reliance on VA primary care 68% 57%

Reliance on VA specialty care 50% 31%
Overview of Medicare Claims

Medicare Claims Data

Identifying Health Care Use in 

Medicare Claims

Common Measures and Research 

Examples

Data Access and Assistance RESEARCHERS’ GUIDE TO VA DATA

Topics for Today

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RESEARCHERS’ GUIDE TO VA DATA

Data Access

VIReC is the data steward for CMS 

(Medicare) data used for VA research

Researchers can request data from 

VIReC’s VA/CMS Data Repository

CMS data are available to VA researchers 

with projects approved by:

– VA Research & Development (R&D) Committee

– Institutional Review Board (IRB)

VA researchers may not obtain CMS data 

directly from CMS/ResDAC

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RESEARCHERS’ GUIDE TO VA DATA

 

Description of CMS data available

Documentation:

– Data dictionaries

– SAS Proc Contents 

– Variable frequencies

Description of cohorts

Links to download Public Use Files

Request Process and Forms

www.virec.research.va.gov/IndexVACMS.htm

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RESEARCHERS’ GUIDE TO VA DATA

 

VIReC Help Desk

– VIReC staff will answer your question and/or 

direct you to available resources on topics

– VIReC@va.gov

HSRData Listserv

– Join at the VIReC Intranet web site

– Discussion among 800+ data stewards, 

managers, and users

– Past messages archived on intranet

www.virec.research.va.gov

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RESEARCHERS’ GUIDE TO VA DATA

 

CMS contractor based at the University of 

Minnesota 

Provides free assistance and training to 

researchers using CMS data

– Help desk

– Knowledge base

– Webinars 

– In-person workshops

www.resdac.org

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RESEARCHERS’ GUIDE TO VA DATA

Run by Buccaneer, a CMS contractor

Source of most CMS data that VHA 

receives

Documentation

– Data dictionaries

– Summary tables

– User guides & technical guides

– White papers & presentations

www.ccwdata.org

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RESEARCHERS’ GUIDE TO VA DATA

Questions?

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RESEARCHERS’ GUIDE TO VA DATA

Upcoming Seminars

February 3, 2014

Pharmacy Data and Medicare Part D

Kevin Stroupe, PhD

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