ArticleBMJ (Clinical research ed.)2015
Massachusetts health reform and disparities in joint replacement use: difference in differences study.
Article in BMJ (Clinical research ed.), 2015. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 15 papers, 1 of them a synthesis that pooled it.
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Who cites it
15 citing papers in PubMed, 1 synthesis or guideline pooled it.
- Examining Timeliness of Total Knee Replacement Among Patients with Knee Osteoarthritis in the U.S.: Results from the OAI and MOST Longitudinal Cohorts.The Journal of bone and joint surgery. American volume · 2020Pooled it
- Exploring China's Clean Air Act and associated cardiovascular disease risk: a prospective, quasi-experimental, and causal inference modelling study.The Lancet. Planetary health · 2026Article
- Legalizing Youth-Friendly Cannabis Edibles and Extracts and Adolescent Cannabis Use.JAMA network open · 2025Article
- Uncemented Tibial Fixation Has Comparable Prognostic Outcomes and Safety Versus Cemented Fixation in Cruciate-Retaining Total Knee Arthroplasty: A Meta-Analysis of Randomized Controlled Trials.Journal of clinical medicine · 2023Review
- Effect of Information Intervention on Prescribing Practice for Neuropathic Pain in Older Patients: A Nationwide Register-Based Study.Drugs & aging · 2023Article
- Changes in Youth Cannabis Use After an Increase in Cannabis Minimum Legal Age in Quebec, Canada.JAMA network open · 2022Article
- SUPPORT-AF III: supporting use of AC through provider prompting about oral anticoagulation therapy for AF.Journal of thrombosis and thrombolysis · 2021Article
- Factors Associated With State-Specific Medicaid Expansion and Receipt of Autologous Breast Reconstruction Among Patients Undergoing Mastectomy.JAMA network open · 2021Article
- Article
- Massachusetts Health Reform's Effect on Hospitalizations with Substance Use Disorder-Related Diagnoses.Health services research · 2018Article
- Impact of Massachusetts Health Reform on Inpatient Care Use: Was the Safety-Net Experience Different Than in the Non-Safety-Net?Health services research · 2017Article
- Did Pre-Affordable Care Act Medicaid Expansion Increase Access to Surgical Cancer Care?Journal of the American College of Surgeons · 2017Article
- Reducing Hospital Readmission Disparities of Older Black and White Adults After Elective Joint Replacement: The Role of Nurse Staffing.Journal of the American Geriatrics Society · 2016Article
- Impact of Expanded Insurance Coverage on Racial Disparities in Vascular Disease: Insights From Massachusetts.Annals of surgery · 2016Article
- Effect of Massachusetts healthcare reform on racial and ethnic disparities in admissions to hospital for ambulatory care sensitive conditions: retrospective analysis of hospital episode statistics.BMJ (Clinical research ed.) · 2015Article
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8 authors.
Funding
Abstract
objectiveTo estimate the impact of the insurance expansion in 2006 on use of knee and hip replacement procedures by race/ethnicity, area income, and the use of hospitals that predominantly serve poor people ("safety net hospitals").
designQuasi-experimental difference in differences study examining change after reform in the share of procedures performed in safety net hospitals by race/ethnicity and area income, with adjustment for patients' residence, demographics, and comorbidity.
settingState of Massachusetts, United States.
participantsMassachusetts residents aged 40-64 as the target beneficiaries of reform and similarly aged residents of New Jersey, New York, and Pennsylvania as the comparison (control) population. MAIN OUTCOMES MEASURES: Number of knee and hip replacement procedures per 10 000 population and use of safety net hospitals. Procedure counts from state discharge data for 2.5 years before and after reform, and multivariate difference in differences. Poisson regression was used to adjust for demographics, economic conditions, secular time, and geographic factors to estimate the change in procedure rate associated with health reform by race/ethnicity and area income.
resultsBefore reform, the number of procedures (/10 000) in Massachusetts was lower among Hispanic people (12.9, P<0.001) than black people (28.1) and white people (30.1). Overall, procedure use increased 22.4% during the 2.5 years after insurance expansion; reform in Massachusetts was associated with a 4.7% increase. The increase associated with reform was significantly higher among Hispanic people (37.9%, P<0.001) and black people (11.4%, P<0.05) than among white people (2.8%). Lower income was not associated with larger increases in procedure use. The share of knee and hip replacement procedures performed in safety net hospitals in Massachusetts decreased by 1.0% from a level of 12.7% before reform. The reduction was larger among Hispanic people (-6.4%, P<0.001) than white people (-1.0%), and among low income residents (-3.9%, p<0.001) than high income residents (0%).
conclusionsInsurance expansion can help reduce disparities by race/ethnicity but not by income in access to elective surgical care and could shift some elective surgical care away from safety net hospitals.
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