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AHRQ Research Studies Date
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- Access to Care (7)
- Children/Adolescents (1)
- Comparative Effectiveness (1)
- Dental and Oral Health (1)
- Disparities (1)
- Domestic Violence (1)
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- (-) Healthcare Cost and Utilization Project (HCUP) (20)
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- Opioids (1)
- Orthopedics (1)
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- Risk (1)
- Surgery (2)
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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 20 of 20 Research Studies DisplayedRamadan OI, Kelz RR, Sharpe JE
Impact of Medicaid expansion on outcomes after abdominal aortic aneurysm repair.
Researchers sought to assess the association between Medicaid expansion and outcomes after abdominal aortic aneurysm repair using HCUP State Inpatient Databases data from 14 states. They examined data on 8995 adult patients under age 65 from both non-expansion states and Medicaid expansion states. The results indicated that Medicaid expansion was associated with decreased in-hospital mortality after abdominal aortic aneurysm repair among all patients, particularly among patients who were either on Medicaid or were uninsured. The researchers concluded that these results provided support for improved access to care for patients undergoing abdominal aortic aneurysm repair through Medicaid expansion.
AHRQ-funded; HS026116.
Citation: Ramadan OI, Kelz RR, Sharpe JE .
Impact of Medicaid expansion on outcomes after abdominal aortic aneurysm repair.
J Vasc Surg 2023 Sep; 78(3):648-56.e6. doi: 10.1016/j.jvs.2023.04.029..
Keywords: Healthcare Cost and Utilization Project (HCUP), Medicaid, Outcomes, Access to Care
Decker S, Dworsky M, Gibson TB
AHRQ Author: Decker S
The Impact of the Affordable Care Act Insurance Expansions on Opioid-Related Emergency Department Visits.
The authors leveraged ACA coverage expansions, including Medicaid expansion and Marketplaces, to study the impact of health insurance on opioid-related emergency department (ED) visits. They used ZIP-code–level ED utilization data from HCUP’s State Inpatient Databases (SID) and State Emergency Department Databases (SEDD) for 29 states. They found evidence of a dose-response relationship between pre-ACA uninsured and changes in ED visit rates in both expansion and non-expansion states: areas with higher uninsured rates prior to ACA saw larger reductions in opioid-related ED visits after the ACA took effect. The authors concluded that these findings suggest that increased insurance coverage may to help mitigate the opioid crisis.
AHRQ-authored.
Citation: Decker S, Dworsky M, Gibson TB .
The Impact of the Affordable Care Act Insurance Expansions on Opioid-Related Emergency Department Visits.
American Journal of Health Economics 2023 Sum; 9(3):405–34..
Keywords: Healthcare Cost and Utilization Project (HCUP), Opioids, Policy, Health Insurance, Emergency Department, Access to Care, Medicaid, Healthcare Utilization
Steenland MW, Wherry LR
Medicaid expansion led to reductions in postpartum hospitalizations.
The purpose of this study was to assess whether the Medicaid expansions of the Affordable Care Act (ACA) affected rates of postpartum hospitalization. The researchers compared states that did and did not expand Medicaid under the ACA as they related to changes in hospitalizations among birthing people with a Medicaid-financed delivery. The study found a 17% reduction in hospitalizations during the first 60 days postpartum associated with the Medicaid expansions, and evidence of a lesser decrease in hospitalizations between 61 days and 6 months postpartum. The researchers concluded that Medicaid coverage expansion under the ACA resulted in improved postpartum health for low-income birthing people.
AHRQ-funded; HS027464.
Citation: Steenland MW, Wherry LR .
Medicaid expansion led to reductions in postpartum hospitalizations.
Health Aff 2023 Jan; 42(1):18-25. doi: 10.1377/hlthaff.2022.00819..
Keywords: Healthcare Cost and Utilization Project (HCUP), Medicaid, Hospitalization, Maternal Care, Women, Health Insurance, Access to Care
Moriya AS, Chakravarty S
AHRQ Author: Moriya AS
Racial and ethnic disparities in preventable hospitalizations and ED visits five years after ACA Medicaid expansions,.
This AHRQ-authored paper examined whether the 2014 Affordable Care Act (ACA) Medicaid expansions mitigated existing racial or ethnic disparities in preventable hospitalizations and emergency department (ED) visits. The authors used inpatient data from twenty-nine states and ED data from twenty-six states for the period 2011 to 2018. They found that Medicaid expansions decreased disparities in preventable hospitalizations and ED visits between non-Hispanic Black and White nonelderly adults by 10 percent or more. There were no significant effects on disparities between Hispanic and non-Hispanic White nonelderly adults. Their findings highlight sustained improvements in community-level care for non-Hispanic Black populations, but also suggest access barriers experienced by Hispanic adults that need to be addressed beyond Medicaid eligibility expansion.
AHRQ-authored.
Citation: Moriya AS, Chakravarty S .
Racial and ethnic disparities in preventable hospitalizations and ED visits five years after ACA Medicaid expansions,.
Health Aff 2023 Jan; 42(1):26-34. doi: 10.1377/hlthaff.2022.00460..
Keywords: Healthcare Cost and Utilization Project (HCUP), Racial and Ethnic Minorities, Emergency Department, Hospitalization, Disparities, Medicaid, Health Insurance, Access to Care
Interrante JD, Tuttle MS, Admon LK
Severe maternal morbidity and mortality risk at the intersection of rurality, race and ethnicity, and Medicaid.
Using maternal discharge records from childbirth hospitalizations in the HCUP National Inpatient Sample, 2007-15, researchers examined differences in rates of severe maternal morbidity and mortality by rural or urban geography, race and ethnicity, and clinical factors among Medicaid-funded births and privately insured hospital births. The highest rate of severe maternal morbidity and mortality occurred among rural Indigenous Medicaid-funded births; births among Black rural and urban residents and among Hispanic urban residents also experienced elevated rates. The researchers concluded that heightened rates of severe maternal morbidity and mortality among Medicaid-funded births indicate an opportunity for state and federal policy responses to address the maternal health challenges faced by Medicaid beneficiaries, including Black, Indigenous, and rural residents
AHRQ-funded; HS027640.
Citation: Interrante JD, Tuttle MS, Admon LK .
Severe maternal morbidity and mortality risk at the intersection of rurality, race and ethnicity, and Medicaid.
Womens Health Issues 2022 Nov-Dec;32(6):540-49. doi: 10.1016/j.whi.2022.05.003..
Keywords: Healthcare Cost and Utilization Project (HCUP), Maternal Care, Women, Pregnancy, Mortality, Risk, Racial and Ethnic Minorities, Medicaid
Greenberg JK, Brown DS, Olsen MA
Association of Medicaid expansion under the Affordable Care Act with access to elective spine surgical care.
This study's goal was to evaluate the impact of Medicaid expansion under the Affordable Care Act on the volume and payer mix of elective spine surgery in the United States. The authors evaluated elective spinal surgeries performed in the U.S. from 2011 to 2016 and included 10 states with expanded Medicaid access and 4 states that did not. They identified 218,648 surgical procedures performed in 10 Medicaid expansion states and 118,693 procedures performed in 4 nonexpansion states. Medicaid expansion was associated with a 17% increase in mean hospital spine surgical volume and a 23% increase in Medicaid volume. Privately insured surgical volumes did not change significantly. This increase indicated improved access to care.
AHRQ-funded; HS027075.
Citation: Greenberg JK, Brown DS, Olsen MA .
Association of Medicaid expansion under the Affordable Care Act with access to elective spine surgical care.
J Neurosurg Spine 2022 Feb;36(2):336–44. doi: 10.3171/2021.3.Spine2122..
Keywords: Healthcare Cost and Utilization Project (HCUP), Medicaid, Access to Care, Surgery
Dy CJ, Salter A, Barker A
Increased utilization of total joint arthroplasty after Medicaid expansion.
This study examined prior analyses that greater utilization of total hip arthroplasty (THA) and total knee arthroplasty (TKA) was to be expected after Medicaid expansion in 2014. Using 2012-2015 data from the HCUP Database, 9 expansion states (Arkansas, Arizona, Colorado, Iowa, Massachusetts, Maryland, Nevada, New York, and Vermont) were compared to 2 states that did not expand Medicaid (Florida and Missouri). After adjusting for community characteristics, THA and TKA increased 15% in 2014 and 23% in 2015 within expansion states compared to 2013. In non-expansion states, compared to 2013, there were significant decreases of 18% in 2014 and 11% in 2015.
AHRQ-funded; HS019455.
Citation: Dy CJ, Salter A, Barker A .
Increased utilization of total joint arthroplasty after Medicaid expansion.
J Bone Joint Surg Am 2021 Mar 17;103(6):524-31. doi: 10.2106/jbjs.20.00303..
Keywords: Healthcare Cost and Utilization Project (HCUP), Medicaid, Orthopedics, Surgery, Healthcare Utilization, Access to Care
Henke RM, Karaca Z, Gibson TB
Medicaid Accountable Care Organizations and childbirth outcomes.
This study examined the impact of Accountable Care Organizations (ACOs) to childbirth outcomes. States that use Medicaid ACOs were compared with states that had not adopted ACO. Using HCUP data, the relationship between Medicaid ACO adoption and neonatal and maternal outcomes, and cost per birth was examined. Medicaid ACO implementation was associated with a moderate reduction in hospital costs per birth and decreased cesarean section rates with results varying by state. There was no association with other birth outcomes, including infant inpatient mortality, low birthweight, neonatal intensive care unit utilization and severe maternal morbidity.
AHRQ-authored; AHRQ-funded; 290201300002C.
Citation: Henke RM, Karaca Z, Gibson TB .
Medicaid Accountable Care Organizations and childbirth outcomes.
Med Care Res Rev 2020 Dec;77(6):559-73. doi: 10.1177/1077558718823132..
Keywords: Healthcare Cost and Utilization Project (HCUP), Medicaid, Health Insurance, Healthcare Costs, Labor and Delivery, Pregnancy, Women, Outcomes
Bucholz EM,, Schuster MA, Toomey SL
Trends in 30-day readmission for Medicaid and privately insured pediatric patients: 2010-2017.
This study examined trends in 30-day readmission rates for Medicaid and privately insured pediatric patients from 2010 to 2017. The HCUP Nationwide Readmissions Database was used to compare hospital-level risk-adjusted readmission rates. Higher readmission rates were found for Medicaid beneficiaires compared to privately insured pediatric patients during the time period.
AHRQ-funded; HS020513; HS025299.
Citation: Bucholz EM,, Schuster MA, Toomey SL .
Trends in 30-day readmission for Medicaid and privately insured pediatric patients: 2010-2017.
Pediatrics 2020 Aug;146(2). doi: 10.1542/peds.2020-0270..
Keywords: Healthcare Cost and Utilization Project (HCUP), Children/Adolescents, Hospital Readmissions, Health Insurance, Medicaid, Hospitals
Pickens G, Karaca Z, Gibson TB
AHRQ Author: Karaca Z, Wong HS
Changes in hospital service demand, cost, and patient illness severity following health reform.
This study examined the effects of expanded Medicaid coverage and the health insurance exchange on the number of hospital inpatient and emergency department (ED) utilization rates, cost, and patient illness severity. There was a significant drop in uninsured inpatient discharges and ED visits in states where Medicaid was expanded. For all by young females, uninsured inpatient discharge rates fell by 39% or greater. In nonexpansion states, the rates remained unchanged or increased slightly. Changes in all-payer and private insurance rates were not as dramatic, as was inpatient costs per discharge and all-payer inpatient costs.
AHRQ-authored; AHRQ-funded; 290201300002C.
Citation: Pickens G, Karaca Z, Gibson TB .
Changes in hospital service demand, cost, and patient illness severity following health reform.
Health Serv Res 2019 Aug;54(4):739-51. doi: 10.1111/1475-6773.13165..
Keywords: Access to Care, Health Insurance, Healthcare Cost and Utilization Project (HCUP), Healthcare Costs, Healthcare Utilization, Hospitals, Medicaid, Policy, Uninsured
Coupet E, Karp D, Wiebe DJ
Shift in U.S. payer responsibility for the acute care of violent injuries after the Affordable Care Act: Implications for prevention.
In this study, the investigators determined the total annual charges for the acute care of injuries from interpersonal violence and the shift in financial responsibility for these charges after the Medicaid expansion from the Affordable Care Act in 2014. After Medicaid expansion, taxpayers are now accountable for nearly half of the $10.7 billion in annual charges for the acute care of violent injury in the U.S. The investigators suggest that these findings highlight the benefit to state Medicaid programs of preventing interpersonal violence.
AHRQ-funded; HS000028.
Citation: Coupet E, Karp D, Wiebe DJ .
Shift in U.S. payer responsibility for the acute care of violent injuries after the Affordable Care Act: Implications for prevention.
Am J Emerg Med 2018 Dec;36(12):2192-96. doi: 10.1016/j.ajem.2018.03.070..
Keywords: Domestic Violence, Emergency Department, Healthcare Costs, Policy, Healthcare Cost and Utilization Project (HCUP), Medicaid
Angraal S, Khera R, Zhou S
Trends in 30-day readmission rates for Medicare and non-Medicare patients in the era of the Affordable Care Act.
In this study the investigators we assessed trends in all-cause readmission rates for 1 of the 3 HRRP conditions or conditions not targeted by the HRRP in age-insurance groups defined by age group (>/=65 years or <65 years) and payer (Medicare, Medicaid, or private insurance). The investigators concluded that there appeared to be a systematic improvement in readmission rates for patient groups beyond the population of fee-for-service, older, Medicare beneficiaries included in the HRRP.
AHRQ-funded; HS022882.
Citation: Angraal S, Khera R, Zhou S .
Trends in 30-day readmission rates for Medicare and non-Medicare patients in the era of the Affordable Care Act.
Am J Med 2018 Nov;131(11):1324-31.e14. doi: 10.1016/j.amjmed.2018.06.013..
Keywords: Policy, Healthcare Cost and Utilization Project (HCUP), Hospital Readmissions, Medicaid, Medicare
Wu VY, Fingar KR, Jiang HJ
AHRQ Author: Jiang HJ
Early impact of the Affordable Care Act coverage expansion on safety-net hospital inpatient payer mix and market shares.
The purpose of the study was to examine the impact of the Affordable Care Act's coverage expansion on safety-net hospitals (SNHs). The investigators concluded that postexpansion, non-SNHs experienced a greater percentage increase in Medicaid stays than did SNHs, which may reflect patients choosing non-SNHs over SNHs or a crowd-out of private insurance.
AHRQ-authored; AHRQ-funded; 290201300002.
Citation: Wu VY, Fingar KR, Jiang HJ .
Early impact of the Affordable Care Act coverage expansion on safety-net hospital inpatient payer mix and market shares.
Health Serv Res 2018 Oct;53(5):3617-39. doi: 10.1111/1475-6773.12812..
Keywords: Policy, Healthcare Cost and Utilization Project (HCUP), Hospitals, Medicaid
Pickens G, Karaca Z, Cutler E
AHRQ Author: Karaca Z, Wong HS
Changes in hospital inpatient utilization following health care reform.
The purpose of this retrospective study was to estimate the effects of 2014 Medicaid expansions on inpatient outcomes using population and unemployment data from HCUP’s State Inpatient Databases. Outcomes included total admissions, referral-sensitive surgical and preventable admissions, length of stay, cost, and severity of patient illness. The authors conclude that Medicaid expansions did not change all-payer admission volumes, but expansions were associated with increased Medicaid and decreased uninsured volumes. The results of the study suggest that previously uninsured persons with a greater need for inpatient services were the most likely to gain coverage.
AHRQ-authored; AHRQ-funded.
Citation: Pickens G, Karaca Z, Cutler E .
Changes in hospital inpatient utilization following health care reform.
Health Serv Res 2018 Jun 30;53(4):2446-69. doi: 10.1111/1475-6773.12734..
Keywords: Healthcare Cost and Utilization Project (HCUP), Hospitalization, Inpatient Care, Medicaid, Policy
Fingar KR, Coffey RM, Mulcahy AW
AHRQ Author: Andrews RM, Stocks C
Shifts in Medicaid and uninsured payer mix at safety-net and non-safety-net hospitals during the Great Recession.
The authors examined payer mix at safety-net hospitals (SNHs) and non-SNHs during a period covering the Great Recession using data from 38 states. The number of privately insured stays decreased at both SNHs and non-SNHs. Non-SNHs increasingly served Medicaid-enrolled and uninsured patients; in SNHs, the number of Medicaid stays decreased and uninsured stays remained stable.
AHRQ-authored; AHRQ-funded; 290201300002C.
Citation: Fingar KR, Coffey RM, Mulcahy AW .
Shifts in Medicaid and uninsured payer mix at safety-net and non-safety-net hospitals during the Great Recession.
J Healthc Manag 2018 May-Jun;63(3):156-72. doi: 10.1097/jhm-d-16-00024.
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Keywords: Healthcare Cost and Utilization Project (HCUP), Hospitals, Medicaid, Uninsured
Berry SA, Fleishman JA, Moore RD
AHRQ Author: Fleishman JA
Thirty-day hospital readmissions for adults with and without HIV infection.
This study compared 30-day readmission rates by HIV status in a multi-state sample with planned subgroup comparisons by insurance and diagnostic categories. After adjustment for age, gender, race, insurance, and diagnostic category, HIV infection was associated with 1.5 times higher odds of readmission. Predicted, adjusted readmission rates were higher for persons living with HIV within every insurance category, including Medicaid.
AHRQ-authored.
Citation: Berry SA, Fleishman JA, Moore RD .
Thirty-day hospital readmissions for adults with and without HIV infection.
HIV Med 2016 Mar;17(3):167-77. doi: 10.1111/hiv.12287.
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Keywords: Healthcare Cost and Utilization Project (HCUP), Human Immunodeficiency Virus (HIV), Hospital Readmissions, Medicaid, Medicare
Hellinger FJ
AHRQ Author: Hellinger FJ
In four ACA expansion states, the percentage of uninsured hospitalizations for people with HIV declined, 2012-14.
This study examines the influence of the Affordable Care Act's optional state Medicaid expansion on insurance coverage and health outcomes for hospitalized patients with HIV. It found that the percentage of hospitalizations of uninsured people with HIV in the four expansion states fell from 13.7 percent to 5.5 percent in the study period, while the percentage in the two nonexpanding states increased from 14.5 percent to 15.7 percent.
AHRQ-authored.
Citation: Hellinger FJ .
In four ACA expansion states, the percentage of uninsured hospitalizations for people with HIV declined, 2012-14.
Health Aff 2015 Dec;34(12):2061-8. doi: 10.1377/hlthaff.2015.0718..
Keywords: Policy, Healthcare Cost and Utilization Project (HCUP), Hospitalization, Human Immunodeficiency Virus (HIV), Medicaid, Uninsured
Fingar KR, Smith MW, Davies S
AHRQ Author: Stocks C
Medicaid dental coverage alone may not lower rates of dental emergency department visits.
This study examined county-level rates of ED visits for nontraumatic dental conditions in twenty-nine States in 2010 in relation to dental provider density and Medicaid coverage of nonemergency dental services. It found that county-level Medicaid-funded dental ED visit rates were lower in states where Medicaid covered nonemergency dental services than in other states, although this difference was not significant after other factors were adjusted for.
AHRQ-authored; AHRQ-funded; 290201200003I; HS021700.
Citation: Fingar KR, Smith MW, Davies S .
Medicaid dental coverage alone may not lower rates of dental emergency department visits.
Health Aff 2015 Aug;34(8):1349-57. doi: 10.1377/hlthaff.2015.0223..
Keywords: Dental and Oral Health, Emergency Department, Healthcare Cost and Utilization Project (HCUP), Comparative Effectiveness, Medicaid
Henke RM, Wier LM, Marder WD
AHRQ Author: Friedman BS, Wong HS
Geographic variation in cesarean delivery in the United States by payer.
This study aimed (1) to determine whether the geographic variation in cesarean delivery rate is consistent for private insurance and Medicaid, and (2) to identify the patient, population, and market factors associated with cesarean rate and determine if these factors vary by payer. It concluded that factors associated with geographic variation in cesarean delivery, a frequent and high-resource inpatient procedure, vary somewhat by payer.
AHRQ-authored; AHRQ-funded; 290200600009C.
Citation: Henke RM, Wier LM, Marder WD .
Geographic variation in cesarean delivery in the United States by payer.
BMC Pregnancy Childbirth 2014 Nov 19;14:387. doi: 10.1186/s12884-014-0387-x.
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Keywords: Healthcare Cost and Utilization Project (HCUP), Health Insurance, Labor and Delivery, Medicaid, Pregnancy
Schiltz NK, Finkelstein Rosenthal B, Crowley MA
Rehospitalization during the first year of life by insurance status.
The authors assessed the association of insurance status on infant rehospitalization in a population-based setting. They found that Medicaid coverage and being uninsured were strong predictors of rehospitalizations, with Medicaid bearing a disproportionate share of the economic burden. Normal birth weight infants had the lowest risk. They further found that jaundice and acute bronchiolitis were the leading causes of rehospitalization within 30 days and 1 year, respectively.
AHRQ-funded; HS000059.
Citation: Schiltz NK, Finkelstein Rosenthal B, Crowley MA .
Rehospitalization during the first year of life by insurance status.
Clin Pediatr 2014 Aug;53(9):845-53. doi: 10.1177/0009922814536924.
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Keywords: Health Insurance, Healthcare Cost and Utilization Project (HCUP), Hospital Readmissions, Newborns/Infants, Medicaid, Newborns/Infants