National Healthcare Quality and Disparities Report
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- Access to Care (1)
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- Low-Income (3)
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AHRQ Research Studies
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Research Studies is a compilation of published research articles funded by AHRQ or authored by AHRQ researchers.
Results
1 to 25 of 40 Research Studies DisplayedSchmittdiel J, Raebel M, Dyer W
Medicare Star excludes diabetes patients with poor CVD risk factor control.
This study is designed to improve understanding of novel CMS quality measures (adherence to antihypertensives, antihyperlipidemics, and oral antihyperglycemics) by assessing the proportion of Medicare patients with diabetes who are excluded from the Medicare Star medication adherence metrics due to early nonadherence and insulin use. Medicare’s STAR measures are used to evaluate the performance of Medicare Advantage plans.
AHRQ-funded; HS019859
Citation: Schmittdiel J, Raebel M, Dyer W .
Medicare Star excludes diabetes patients with poor CVD risk factor control.
Am J Manag Care. 2014 Dec; 20(12):e573-81..
Keywords: Medicare, Diabetes, Quality Measures, Patient Adherence/Compliance
Bilchick KC, Stukenborg GJ
Comparative effectiveness of cardiac resynchronization therapy in combination with implantable defibrillator in patients with heart failure and wide QRS duration.
The researchers examined the long-term outcomes among Medicare patients with cardiac resynchronization therapy defibrillators (CRT-D) compared with those receiving standard implantable cardioverter defibrillators. They found that the greatest benefit of CRT-D was in patients with guideline-based class I recommendations for CRT-D. For these patients, there was a 17 percent reduction in risk of death.
AHRQ-funded; HS017693
Citation: Bilchick KC, Stukenborg GJ .
Comparative effectiveness of cardiac resynchronization therapy in combination with implantable defibrillator in patients with heart failure and wide QRS duration.
Am J Cardiol. 2014 Nov 15;114(10):1537-42. doi: 10.1016/j.amjcard.2014.08.017..
Keywords: Comparative Effectiveness, Medicare, Outcomes, Cardiovascular Conditions, Medical Devices
Du DT, McKean SJ, Kelman JA, et al.
AHRQ Author: Encinosa W
Early mortality after aortic valve replacement with mechanical prosthetic vs bioprosthetic valves among Medicare beneficiaries: a population-based cohort study.
The researchers compared early mortality after aortic valve replacement (AVR) between the recipients of mechanical and bioprosthetic aortic valves. Among 66,453 Medicare beneficiaries who received AVRs, use of mechanical valves was associated with a higher risk for death on the date of surgery and within 30 days compared with the bioprosthetic aortic valves. However, this applied only to those who underwent concurrent AVR and coronary artery bypass graft but not isolated AVR.
AHRQ-authored
Citation: Du DT, McKean SJ, Kelman JA, et al..
Early mortality after aortic valve replacement with mechanical prosthetic vs bioprosthetic valves among Medicare beneficiaries: a population-based cohort study.
JAMA Intern Med. 2014 Nov;174(11):1788-95. doi: 10.1001/jamainternmed.2014.4300..
Keywords: Cardiovascular Conditions, Medicare, Mortality, Patient-Centered Outcomes Research, Surgery
Trish E, Joyce G, Goldman DP
Specialty drug spending trends among Medicare and Medicare Advantage enrollees, 2007-11.
The authors analyzed trends in specialty drug spending among Medicare beneficiaries ages sixty-five and older using 2007-11 pharmacy claims data. They found that annual specialty drug spending per beneficiary who used specialty drugs increased considerably during the study period, but specialty drugs accounted for less than ten percent of total drug spending per beneficiary. Additionally, in 2011, cost-sharing reductions under the Affordable Care Act significantly reduced specialty drug users' out-of-pocket burden, which decreased 26 percent from 2010.
AHRQ-funded; HS000046.
Citation: Trish E, Joyce G, Goldman DP .
Specialty drug spending trends among Medicare and Medicare Advantage enrollees, 2007-11.
Health Aff 2014 Nov;33(11):2018-24. doi: 10.1377/hlthaff.2014.0538.
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Keywords: Healthcare Costs, Health Insurance, Medicare, Medication
Calderwood MS, Kleinman K, Bratzler DW
Medicare claims can be used to identify US hospitals with higher rates of surgical site infection following vascular surgery.
This study found that among Medicare patients who underwent vascular surgery at 2,512 U.S. hospitals, a patient undergoing surgery in a hospital ranked in the worst-performing decile based on claims had a 2.5 times greater likelihood of developing a chart-confirmed surgical site infection relative to a patient characteristics in a hospital in the best-performing decile.
AHRQ-funded; HS018878
Citation: Calderwood MS, Kleinman K, Bratzler DW .
Medicare claims can be used to identify US hospitals with higher rates of surgical site infection following vascular surgery.
Med Care. 2014 Oct;52(10):918-25. doi: 10.1097/MLR.0000000000000212..
Keywords: Medicare, Surgery, Healthcare-Associated Infections (HAIs), Patient Safety, Hospitals, Adverse Events
Chaudhry SI, Khan RF, Chen J
National trends in recurrent AMI hospitalizations 1 year after acute myocardial infarction in Medicare beneficiaries: 1999-2010.
The investigators evaluated changes in the incidence of 1-year recurrent acute myocardial infarction (AMI) hospitalization and mortality. In a national sample of Medicare beneficiaries hospitalized for AMI from 1999 to 2010, they found that hospitalization for recurrent AMI decreased, as did subsequent mortality, albeit to a lesser extent. The risk of recurrent AMI hospitalization declined less in black patients than in whites, increasing observed racial disparities by the end of the study period.
AHRQ-funded; HS018781.
Citation: Chaudhry SI, Khan RF, Chen J .
National trends in recurrent AMI hospitalizations 1 year after acute myocardial infarction in Medicare beneficiaries: 1999-2010.
J Am Heart Assoc 2014 Oct;3(5):e001197. doi: 10.1161/jaha.114.001197.
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Keywords: Hospitalization, Medicare, Mortality, Heart Disease and Health, Risk
Eckenrode S, Bakullari A, Metersky ML
The association between age, sex, and hospital-acquired infection rates: results from the 2009-2011 National Medicare Patient Safety Monitoring System.
The researchers, using six different measures of hospital-acquired infections (HAIs), analyzed data from a large national sample of patients admitted to the hospital with acute cardiovascular disease, pneumonia, and major surgery to determine to determine age- and sex-related differences in HAI rates. They found that there are no simple ways to focus HAI-prevention efforts based solely on age or sex.
AHRQ-funded; 290201200003C
Citation: Eckenrode S, Bakullari A, Metersky ML .
The association between age, sex, and hospital-acquired infection rates: results from the 2009-2011 National Medicare Patient Safety Monitoring System.
Infect Control Hosp Epidemiol. 2014 Oct;35 Suppl 3:S3-9. doi: 10.1086/677831..
Keywords: Healthcare-Associated Infections (HAIs), Patient Safety, Medicare, Critical Care
Cook EA, Schneider KM, Robinson J
Field methods in medical record abstraction: assessing the properties of comparative effectiveness estimates.
Comparative effectiveness studies using Medicare claims data are vulnerable to treatment selection biases and supplemental data from a sample of patients has been recommended for examining the magnitude of this bias. The investigators collected medical record data from a subsample of patients to assess the validity of assumptions and to aid in the interpretation of our estimates. In this paper, they sought to describe and document the process used to collect and validate this supplemental information.
AHRQ-funded; HS018381.
Citation: Cook EA, Schneider KM, Robinson J .
Field methods in medical record abstraction: assessing the properties of comparative effectiveness estimates.
BMC Health Serv Res 2014 Sep 15;14:391. doi: 10.1186/1472-6963-14-391..
Keywords: Comparative Effectiveness, Medicare, Evidence-Based Practice, Research Methodologies
Sharma R, Lebrun-Harris LA, Ngo-Metzger Q
AHRQ Author: Ngo-Metzger Q
Costs and clinical quality among Medicare beneficiaries: associations with health center penetration of low-income residents.
The authors determined the association between access to primary care by the underserved and Medicare spending and clinical quality across hospital referral regions (HRRs). They found that, compared with elderly fee-for-service beneficiaries residing in areas with low-penetration of health center patients among low-income residents, those residing in high-penetration areas may accrue Medicare cost savings.
AHRQ-authored.
Citation: Sharma R, Lebrun-Harris LA, Ngo-Metzger Q .
Costs and clinical quality among Medicare beneficiaries: associations with health center penetration of low-income residents.
Medicare Medicaid Res Rev 2014 Sep 8;4(3). doi: 10.5600/mmrr.004.03.a05.
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Keywords: Access to Care, Community-Based Practice, Quality of Care, Low-Income, Medicare
Borne RT, Peterson PN, Greenlee R
Temporal trends in patient characteristics and outcomes among Medicare beneficiaries undergoing primary prevention implantable cardioverter-defibrillator placement in the United States, 2006-2010.
Results from the National Cardiovascular Data Registry's Implantable Cardioverter-Defibrillator Registry. This study characterizing trends in clinical profiles and outcomes among Medicare patients undergoing primary implantable cardioverter-defibrillator implantation found only modest changes in clinical characteristics between 2006 and 2010. However, 6-month mortality and rehospitalization improved significantly over time, suggesting that there were meaningful improvements.
AHRQ-funded; HS019814
Citation: Borne RT, Peterson PN, Greenlee R .
Temporal trends in patient characteristics and outcomes among Medicare beneficiaries undergoing primary prevention implantable cardioverter-defibrillator placement in the United States, 2006-2010.
Circulation. 2014 Sep 2;130(10):845-53. doi: 10.1161/CIRCULATIONAHA.114.008653..
Keywords: Medical Devices, Outcomes, Medicare, Registries, Quality of Care
Yehia BR, Fleishman JA, Agwu AL
AHRQ Author: Fleishman JA
Health insurance coverage for persons in HIV care, 2006-2012.
The authors examined trends in health insurance coverage at 11 US HIV clinics between 2006 and 2012. They found that Medicaid coverage was more prevalent among women than men; blacks and Hispanics than whites; and individuals with injection drug use risk compared with other transmission risk factors, with Hispanics and younger age groups more likely to be uninsured than other racial/ethnic and older age groups, respectively.
AHRQ-authored; AHRQ-funded; 290201100007C.
Citation: Yehia BR, Fleishman JA, Agwu AL .
Health insurance coverage for persons in HIV care, 2006-2012.
J Acquir Immune Defic Syndr 2014 Sep 1;67(1):102-6. doi: 10.1097/qai.0000000000000251.
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Keywords: Health Insurance, Human Immunodeficiency Virus (HIV), Medicare, Racial and Ethnic Minorities, Uninsured
Kronick R, Welch WP
AHRQ Author: Kronick R
Measuring coding intensity in the Medicare Advantage program.
Each year from 2004-2013, the average Medicare Advantage risk score increased faster than the average fee-for-service score. The intensity of coding varies widely by contract. The authors suggested that with the continuous relative increase in the average Medicare Advantage risk score, further policy changes will likely be necessary.
AHRQ-authored.
Citation: Kronick R, Welch WP .
Measuring coding intensity in the Medicare Advantage program.
Medicare Medicaid Res Rev 2014 Jul 17;4(2). doi: 10.5600/mmrr2014-004-02-a06.
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Keywords: Medicare, Health Insurance, Payment
Daiello LA, Gardner R, Epstein-Lubow G
Association of dementia with early rehospitalization among Medicare beneficiaries.
This study examined the question of whether dementia was associated with a greater likelihood of Medicare patients being readmitted to the hospital within 30 days. Using a group of 25,839 hospitalizations, including 3,908 admissions of Me.icare beneficiaries with dementia, it found that those with a dementia diagnosis were more likely (17.8 percent vs. 14.5 percent) to be readmitted within 30 days.
AHRQ-funded; HS017735.
Citation: Daiello LA, Gardner R, Epstein-Lubow G .
Association of dementia with early rehospitalization among Medicare beneficiaries.
Arch Gerontol Geriatr. 2014 Jul-Aug;59(1):162-8. doi: 10.1016/j.archger.2014.02.010..
Keywords: Medicare, Elderly, Dementia, Hospital Readmissions
Schwartz AL, Landon BE, Elshaug AG
Measuring low-value care in Medicare.
To study health care overuse, this study developed claims-based measures of low-value services ranging from low-value cancer screening and preoperative testing to low-value surgical procedures. Services detected by a limited number of measures of low-value care constituted modest proportions of overall spending, but affected substantial proportions of Medicare beneficiaries and may reflect overuse.
AHRQ-funded; HS00055
Citation: Schwartz AL, Landon BE, Elshaug AG .
Measuring low-value care in Medicare.
JAMA Intern Med. 2014 Jul;174(7):1067-76. doi: 10.1001/jamainternmed.2014.1541..
Keywords: Medicare, Healthcare Costs
Kumamaru H, Judd SE, Curtis JR
Validity of claims-based stroke algorithms in contemporary Medicare data: reasons for geographic and racial differences in stroke (REGARDS) study linked with medicare claims.
The researchers assessed the validity of diagnostic coding algorithms for identifying stroke in the Medicare population by linking data from the REasons for Geographic And Racial Differences in Stroke (REGARDS) Study to Medicare claims. They found that claims-based algorithms to identify stroke in a contemporary Medicare cohort had high positive predictive value and specificity, supporting their use as outcomes for etiologic and comparative effectiveness studies in similar populations.
AHRQ-funded; HS017731; HS018517.
Citation: Kumamaru H, Judd SE, Curtis JR .
Validity of claims-based stroke algorithms in contemporary Medicare data: reasons for geographic and racial differences in stroke (REGARDS) study linked with medicare claims.
Circ Cardiovasc Qual Outcomes 2014 Jul;7(4):611-9. doi: 10.1161/circoutcomes.113.000743..
Keywords: Stroke, Medicare, Comparative Effectiveness, Outcomes
Zhang Y, Zhou C, Baik SH
A simple change to the Medicare Part D low-income subsidy program could save $5 billion.
The authors used an intelligent reassignment algorithm and 2008-09 Medicare Part D drug use and spending data to match enrollees to available Part D plans according to their medication needs. They found that such a reassignment approach, compared to the current approach, could have saved the federal government over $5 billion in 2009.
AHRQ-funded; HS018657.
Citation: Zhang Y, Zhou C, Baik SH .
A simple change to the Medicare Part D low-income subsidy program could save $5 billion.
Health Aff 2014 Jun;33(6):940-5. doi: 10.1377/hlthaff.2013.1083.
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Keywords: Healthcare Costs, Low-Income, Medicare, Medication
Tong L, Ahn C, Symanski E
Effects of newly developed chemotherapy regimens, comorbidities, chemotherapy-related toxicities on the changing patterns of the leading causes of death in elderly patients with colorectal cancer.
This study examined the effects of newly developed chemotherapy regimens, comorbidities, and chemotherapy-related toxicities on the changing patterns of the leading causes of death in elderly patients with colorectal cancer (CRC). It found that the risks of CRC-specific death decreased with diagnostic time periods only in chemotherapy recipients.
AHRQ-funded; HS018956
Citation: Tong L, Ahn C, Symanski E .
Effects of newly developed chemotherapy regimens, comorbidities, chemotherapy-related toxicities on the changing patterns of the leading causes of death in elderly patients with colorectal cancer.
Ann Oncol. 2014 Jun;25(6):1234-42. doi: 10.1093/annonc/mdu131..
Keywords: Elderly, Mortality, Treatments, Medicare
Rocke DJ, Beumer HW, Taylor DH, Jr.
Physician and patient and caregiver health attitudes and their effect on Medicare resource allocation for patients with advanced cancer.
The investigators sought to determine how baseline attitudes toward quality vs quantity of life affect end-of-life resource allocation. They found that, compared with patients and caregivers, otolaryngology-head and neck surgery (OHNS) physician allocations differed significantly in all 15 benefit categories except home care. They concluded that understanding the effect of baseline attitudes is important for effective end-of-life discussions.
AHRQ-funded; HS018360.
Citation: Rocke DJ, Beumer HW, Taylor DH, Jr. .
Physician and patient and caregiver health attitudes and their effect on Medicare resource allocation for patients with advanced cancer.
JAMA Otolaryngol Head Neck Surg 2014 Jun;140(6):497-503. doi: 10.1001/jamaoto.2014.494.
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Keywords: Cancer, Caregiving, Medicare, Palliative Care, Provider: Physician, Quality of Life
Setoguchi SR, Warner Stevenson L, Stewart GC
Influence of healthy candidate bias in assessing clinical effectiveness for implantable cardioverter-defibrillators: cohort study of older patients with heart failure.
This study assessed the potential contribution of unmeasured general health status to patient selection in assessments of implantable cardioverter-defibrillator (ICD) therapy. In a group of heart failure patients, those who received ICD therapy were younger and had lower ejection fraction and more cardiac admissions to hospital but fewer non-cardiac admissions. The lower risks of measured outcomes likely reflect unmeasured differences in comorbidity and frailty.
AHRQ-funded; 29020050016I; HS017731
Citation: Setoguchi SR, Warner Stevenson L, Stewart GC .
Influence of healthy candidate bias in assessing clinical effectiveness for implantable cardioverter-defibrillators: cohort study of older patients with heart failure.
BMJ. 2014 May 8;348:g2866. doi: 10.1136/bmj.g2866..
Keywords: Medical Devices, Outcomes, Registries, Heart Disease and Health, Medicare
Hays RD, Berman LJ, Kanter MH
Evaluating the psychometric properties of the CAHPS Patient-Centered Medical Home survey.
This study surveyed Medicare beneficiaries to evaluate the reliability and validity of a new five-item care coordination measure. The composite score had a strong unique association with the CAHPS global rating of health care, after controlling for the CAHPS core composite scores.
AHRQ-funded; HS016980
Citation: Hays RD, Berman LJ, Kanter MH .
Evaluating the psychometric properties of the CAHPS Patient-Centered Medical Home survey.
Clin Ther. 2014 May;36(5):689-696.e1. doi: 10.1016/j.clinthera.2014.04.004..
Keywords: Consumer Assessment of Healthcare Providers and Systems (CAHPS), Quality of Care, Medicare, Patient Experience, Patient-Centered Healthcare
McGarry BE, Strawderman RL, Li Y
Lower Hispanic participation in Medicare Part D may reflect program barriers.
This study found that Hispanics were 35 percent less likely than non-Hispanic whites to have Medicare Part D coverage. This difference may be driven by ethnic disparities among those eligible for the low-income Part D subsidy but not automatically enrolled in it.
AHRQ-funded; HS00044
Citation: McGarry BE, Strawderman RL, Li Y .
Lower Hispanic participation in Medicare Part D may reflect program barriers.
Health Aff. 2014 May;33(5):856-62. doi: 10.1377/hlthaff.2013.0671..
Keywords: Medicare, Disparities, Racial and Ethnic Minorities, Low-Income, Healthcare Costs
Setoguchi S, Zhu Y, Jalbert JJ
Validity of deterministic record linkage using multiple indirect personal identifiers: linking a large registry to claims data.
The researchers compared the validity of several deterministic record linkage methods with multiple indirect identifiers by using data from the Centers for Medicare and Medicaid Services (CMS) implantable cardioverter-defibrillator (ICD) registry and administrative Medicare inpatient claims data. Linkage rules using 2 or 3 indirect, patient-level identifiers and hospital ID produced linkages with sensitivity of 95% and specificity of 98% compared with a gold standard linkage rule.
AHRQ-funded; 29020050016I; HS017731.
Citation: Setoguchi S, Zhu Y, Jalbert JJ .
Validity of deterministic record linkage using multiple indirect personal identifiers: linking a large registry to claims data.
Circ Cardiovasc Qual Outcomes 2014 May;7(3):475-80. doi: 10.1161/circoutcomes.113.000294..
Keywords: Medical Devices, Medicare, Registries, Data, Inpatient Care
Thacker EL, Muntner P, Zhao H
Claims-based algorithms for identifying Medicare beneficiaries at high estimated risk for coronary heart disease events: a cross-sectional study.
The researchers sought to develop claims-based algorithms to identify individuals at high risk for coronary artery disease (CHD) and to identify low-density lipoprotein (LDL) cholesterol among statin users at high risk for CHD events. They found that despite low sensitivity, the high predictive value of their algorithm for high risk for CHD events supports the use of claims to identify Medicare beneficiaries at high risk for CHD events.
AHRQ-funded; HS018517
Citation: Thacker EL, Muntner P, Zhao H .
Claims-based algorithms for identifying Medicare beneficiaries at high estimated risk for coronary heart disease events: a cross-sectional study.
BMC Health Serv Res. 2014 Apr 29;14:195. doi: 10.1186/1472-6963-14-195..
Keywords: Comparative Effectiveness, Medicare, Risk, Cardiovascular Conditions, Chronic Conditions
Martin BI, Lurie JD, Tosteson AN
Indications for spine surgery: validation of an administrative coding algorithm to classify degenerative diagnoses.
The Spine Patient Outcomes Research Trial (SPORT) provided a unique opportunity to examine the validity of a claims-based algorithm for grouping patients by surgical indication. SPORT enrolled patients for lumbar disc herniation, spinal stenosis, and degenerative spondylolisthesis. The researchers found that their claims-based hierarchical coding algorithm of spine-related medical encounters correctly classified more than 90 percent of Medicare patients into their respective SPORT cohorts.
AHRQ-funded; HS018405
Citation: Martin BI, Lurie JD, Tosteson AN .
Indications for spine surgery: validation of an administrative coding algorithm to classify degenerative diagnoses.
Spine. 2014 Apr 20;39(9):769-79. doi: 10.1097/brs.0000000000000275..
Keywords: Comparative Effectiveness, Surgery, Outcomes, Medicare
Chrischilles E, Schneider K, Wilwert J
Beyond comorbidity: expanding the definition and measurement of complexity among older adults using administrative claims data.
Studies of patients with multiple chronic conditions using claims data are often missing important determinants of treatments and outcomes, such as function status and disease severity. In this study, the investigators sought to identify and evaluate a class of function-related indicators (FRIs) from administrative claims data. The investigators concluded that claims data studies that include indicators of potentially diminished patient functional status better capture heterogeneity of patients with multiple chronic conditions.
AHRQ-funded; HS019440.
Citation: Chrischilles E, Schneider K, Wilwert J .
Beyond comorbidity: expanding the definition and measurement of complexity among older adults using administrative claims data.
Med Care 2014 Mar;52(Suppl 3):S75-S84. doi: 10.1097/mlr.0000000000000026..
Keywords: Elderly, Chronic Conditions, Medicare