Health Services Research最新文献

{"title":"Transporting difference-in-differences estimates to assess health equity impacts of payment and delivery models.","authors":"Katherine Ianni, Alyssa Chen, Daniela Rodrigues, Laura A Hatfield","doi":"10.1111/1475-6773.14419","DOIUrl":"https://doi.org/10.1111/1475-6773.14419","url":null,"abstract":"<p><strong>Objective: </strong>To demonstrate the use of transportability methods to extend findings from payment model evaluations to groups of historically underserved beneficiaries.</p><p><strong>Study setting and design: </strong>We used a simulation study to transport the effects of the Comprehensive Primary Care Plus (CPC+) model to a target population of Black fee-for-service (FFS) Medicare beneficiaries living outside the original 18 CPC+ regions. Our main outcome variable was total Medicare spending per beneficiary per year (pbpy).</p><p><strong>Data sources and analytic sample: </strong>We simulated practice-level spending in 18 CPC+ regions and 32 non-CPC+ regions (1200 practices per region). We calibrated the simulation parameters to values from the literature and then varied four key parameters to create 16 realistic simulation scenarios. These scenarios varied the representativeness of practices in CPC+ regions that joined CPC+ (i.e., the sample) relative to the target population by changing the distribution of Black beneficiaries across practices and the distribution of practices across regions. Practices were characterized by their experience with the Medicare Shared Savings Program (SSP) and system/hospital ownership because these are known to modify the effect of CPC+ on spending.</p><p><strong>Principal findings: </strong>Across the 16 simulation scenarios, transporting the treatment effect of CPC+ to Black FFS beneficiaries in non-CPC+ regions yielded median treatment effects that ranged from $15.5 pbpy smaller to $10 pbpy larger than in the sample. These differences are roughly the same magnitude as the estimated overall effect of $13 pbpy.</p><p><strong>Conclusions: </strong>The Center for Medicare and Medicaid Innovation has pledged to put equity at the center of its demonstration models. However, offering models in limited geographic areas with voluntary provider participation may result in unrepresentative samples. Naively generalizing CPC+ effects from geographically limited, voluntary samples to all Black FFS beneficiaries could be misleading. Under some circumstances, transportability methods can be used to estimate effects in this target population.</p>","PeriodicalId":55065,"journal":{"name":"Health Services Research","volume":" ","pages":"e14419"},"PeriodicalIF":3.1,"publicationDate":"2024-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142866498","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Improving perinatal depression screening uptake: The impact of Medicaid reimbursement policy in Massachusetts.","authors":"Chanup Jeung, Laura B Attanasio, Kimberley H Geissler","doi":"10.1111/1475-6773.14420","DOIUrl":"https://doi.org/10.1111/1475-6773.14420","url":null,"abstract":"<p><strong>Objective: </strong>To evaluate the impact of the Massachusetts Medicaid program's reimbursement policy change for perinatal depression screening on utilization rates.</p><p><strong>Study setting and design: </strong>This study employed a difference-in-differences design to compare insurance-paid prenatal and postpartum depression screening rates as well as postpartum antidepressant receipt rates between Medicaid and privately insured individuals before and after policy implementation in May 2016.</p><p><strong>Data sources and analytic sample: </strong>Data are from the 2014-2020 Massachusetts All-Payer Claims Database. The study included individuals with a live birth from October 10, 2014, to December 31, 2019, who were continuously insured either by Medicaid or private insurance.</p><p><strong>Principal findings: </strong>Among 141,085 births, 42.6% were covered by Medicaid. Among those with Medicaid, 1.9% had a paid postpartum depression screening prior to the policy and 16.9% after (1.5% vs. 12.3% for prenatal screening); among privately insured, 3.8% had a paid postpartum screening prior to the policy and 10.6% after (0.9% vs. 6.7% for prenatal screening). Antidepressant receipt rose from 6.9% to 8.3% among Medicaid enrollees and from 3.3% to 4.9% among privately insured individuals after the policy. After regression adjustment, implementation of the Massachusetts Medicaid reimbursement policy was positively associated with perinatal depression screening rates with a differential increase of 10.0 percentage points (p < 0.001) for postpartum screening and 3.5 percentage points (p < 0.001) for prenatal screening among Medicaid enrollees versus privately insured. Despite increased depression screening, the policy was not associated with a statistically significant change in antidepressant receipt among Medicaid enrollees compared to privately insured individuals.</p><p><strong>Conclusions: </strong>Separate payment for perinatal depression screening significantly improved screening rates among Medicaid beneficiaries, highlighting Medicaid's critical role in identifying mental health needs for vulnerable populations. However, the persistence of sub-optimal screening rates among perinatal individuals underscores the need for a comprehensive approach to ensure universal screening and effective treatment for perinatal depression.</p>","PeriodicalId":55065,"journal":{"name":"Health Services Research","volume":" ","pages":"e14420"},"PeriodicalIF":3.1,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142840369","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sustainability of California's Whole Person Care pilots integrating medical and social services for Medicaid enrollees via newly developed Medicaid benefits.","authors":"Nadia Safaeinili, Emmeline Chuang, Mark Fleming, Shoba Ramanadhan, Nadereh Pourat, Amanda Brewster","doi":"10.1111/1475-6773.14418","DOIUrl":"https://doi.org/10.1111/1475-6773.14418","url":null,"abstract":"<p><strong>Objective: </strong>To assess multi-level factors influencing the sustainability of 26 social care pilots integrating medical and social services for Medicaid enrollees across California in newly developed Medicaid benefits.</p><p><strong>Study setting and design: </strong>This qualitative study assessed the sustainability of Whole Person Care (WPC) pilots implemented between 2016 and 2021. Pilots (n = 26) represented a majority of counties in California.</p><p><strong>Data sources and analytic sample: </strong>Primary qualitative data were collected between June and August 2021 and included 58 hour-long, semi-structured individual and group interviews with administrators, middle managers, and frontline case management staff representing all WPC pilots. We used hybrid inductive-deductive thematic analysis to identify and analyze patterns, and outliers, in factors influencing sustainment. Deductive codes included established implementation science factors influencing the sustainability of new programs (e.g., innovation characteristics, capacity, processes and interactions, and context).</p><p><strong>Principal findings: </strong>Of 26 WPC pilots, 22 pilots sustained WPC by contracting with Medicaid managed care plans to provide services as part of newly developed Medicaid benefits. Three pilots chose not to sustain before the pilot period ended and one pilot decided not to sustain following completion of the full pilot. Factors influencing sustainability included: (1) program adaptability and flexibility; (2) funding structure and reimbursement requirements; (3) shared leadership with managed care plans; and (4) whether pilots chose to build out program infrastructure internally or contracted out core components to partner organizations. Many pilots, particularly those in rural areas, indicated that system and policy changes introduced as part of transitioning pilot services into Medicaid benefits reduced the sustainability of WPC for participating providers.</p><p><strong>Conclusions: </strong>Multi-level factors including program adaptability, funding, leadership, and capacity to build out infrastructure influenced the sustainability of WPC pilots. These findings have significant implications for health equity as equitable distribution of services, resources, and benefits from these programs can be supported through sustained implementation over time.</p>","PeriodicalId":55065,"journal":{"name":"Health Services Research","volume":" ","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-12-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142819941","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Telehealth and disparities in opioid use disorder treatment: Medicaid enrollees versus privately insured individuals.","authors":"Lindsay D Allen, Melinda Xu","doi":"10.1111/1475-6773.14414","DOIUrl":"https://doi.org/10.1111/1475-6773.14414","url":null,"abstract":"<p><strong>Objective: </strong>To determine how the rise of telehealth during the COVID-19 pandemic impacted Medicaid enrollees' access to opioid use disorder (OUD) treatment.</p><p><strong>Data sources and study setting: </strong>Electronic health records from Northwestern Medicine, a large midwestern academic health system, from January 1, 2019 to December 31, 2021.</p><p><strong>Study design: </strong>The exposure was the expansion of telehealth services during the COVID-19 pandemic. A difference-in-differences design was used to determine the impact of telehealth on the probability of receiving any OUD care, any in-person OUD care, and any telehealth OUD care in a month.</p><p><strong>Data collection/extraction methods: </strong>The study included Medicaid and privately insured patients older than 18 years of age, diagnosed with OUD, who had any encounter with the Northwestern Medicine system. All outpatient visits with OUD as the primary diagnosis were included in the analysis. There were 486 individuals in the sample and 17,496 person-month observations.</p><p><strong>Principal findings: </strong>After the onset of the COVID-19 pandemic, Medicaid enrollees are 4.5 percentage points (percentage change, 43.7%; 95% confidence interval [CI] 8.7 to 0.3 percentage points; p = 0.035) less likely to receive any OUD care in a month, relative to privately insured patients. While no statistically significant differences in the likehood of receiving in-person OUD care were detected between the groups after exposure, we did observe that Medicaid enrollees are 3.6 percentage points (percentage change 64.2%; 95% CI 6.0 to 1.1 percentage points; p = 0.004) less likely to receive any telehealth OUD care in a month relative to privately insured patients.</p><p><strong>Conclusions: </strong>While those with private insurance were able to maintain OUD treatment during the pandemic by supplementing in-person care with telehealth, Medicaid enrollees experienced a drop in overall OUD treatment rates due to lower telehealth use. The rise of telehealth for OUD treatment might contribute to widening care gaps for Medicaid enrollees.</p>","PeriodicalId":55065,"journal":{"name":"Health Services Research","volume":" ","pages":"e14414"},"PeriodicalIF":3.1,"publicationDate":"2024-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142803545","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The relationship between food and housing insecurity and healthcare use among Virginia Medicaid expansion members: Considering the neighborhood context.","authors":"Hannah Shadowen, Sarah J Marks, Olufemi Obembe, Andrew Mitchell, Chethan Bachireddy, Anika Hines, Roy Sabo, Peter Cunningham, Alex Krist, Andrew Barnes","doi":"10.1111/1475-6773.14416","DOIUrl":"https://doi.org/10.1111/1475-6773.14416","url":null,"abstract":"<p><strong>Objective: </strong>To understand relationships between healthcare use and food and housing insecurity in Medicaid expansion members, as well as whether these relationships differ by rurality or residential segregation.</p><p><strong>Data sources and study setting: </strong>Database of Virginia Medicaid expansion members from the Department of Medical Assistance Services. Sample included individuals who enrolled January-June 2019, were aged 19-64 years, remained continuously enrolled for 12 months, and completed a Medicaid Member Health Screening (MMHS) conducted within the first 3 months of enrollment (n = 14,735).</p><p><strong>Study design: </strong>Retrospective cohort study. Outcomes included any primary care visits (PC) and any emergency department (ED) visits in the first 12 months of enrollment. The MMHS sample was weighted to represent all Medicaid expansion members (n = 234,296). Separate multivariable linear probability models regressed having any PC or ED visits on food and housing insecurity controlling for individual and neighborhood characteristics. Models were then stratified by rurality and racial residential segregation.</p><p><strong>Data collection: </strong>None.</p><p><strong>Principal findings: </strong>Food insecurity was negatively associated with having any PC visit (-2.9 percentage points (PP); p-value <0.01) and positively associated with having any ED visit (7.0 PP; p-value <0.001). No significant relationships between PC or ED visits and housing insecurity were found. Suburban and urban individuals with food insecurity were significantly less likely to have any PC visit (p < 0.05 each). Medicaid expansion members living in disproportionately low-income or mixed-income neighborhoods experiencing food insecurity were also less likely to have any PC visits (p < 0.05), and the same was not true for those living in disproportionately high-income neighborhoods.</p><p><strong>Conclusions: </strong>Food insecurity among Medicaid expansion members is associated with less primary care and more emergency department use, but these relationships differ by the neighborhoods in which members live. Medicaid agency efforts that coordinate medical and social service benefits and also consider local context may further increase access to necessary and appropriate care.</p>","PeriodicalId":55065,"journal":{"name":"Health Services Research","volume":" ","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142787819","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Collaboration strategies for bridging health, behavioral health, and social services in California's Medi-Cal Whole Person Care Pilot Program.","authors":"Emmeline Chuang, Rachel Ross, Nadia Safaeinili, Leigh Ann Haley, Brenna O'Masta, Nadereh Pourat","doi":"10.1111/1475-6773.14417","DOIUrl":"https://doi.org/10.1111/1475-6773.14417","url":null,"abstract":"<p><strong>Objective: </strong>To identify collaboration strategies used to integrate health, behavioral health, and social services for Medicaid members in California's Medi-Cal Whole Person Care Pilot program (WPC).</p><p><strong>Data sources and study setting: </strong>WPC was a social care intervention implemented to identify and address eligible members' health, behavioral health, and social needs. Data included semi-structured key informant interviews conducted in 2018-2019 (n = 221) and 2021 (n = 167); pilot-level surveys; whole-network surveys of 507 organizations in all 25 pilots participating in WPC; and documents submitted by pilots to the state. Pilots served a total of 247,887 unique members between 2017 and 2021, the majority of whom were non-white (72%) and over half of whom experienced homelessness.</p><p><strong>Study design/data collection: </strong>Data were collected as part of the statewide evaluation of WPC. We analyzed qualitative data to examine strategies used by pilots to integrate care, network data to identify pilots that improved cross-sector collaboration (i.e., strengthened density or multiplexity of cross-sector ties) following WPC implementation, and comparative case analysis to identify strategies that differentiated pilots that improved collaboration from those that did not.</p><p><strong>Principal findings: </strong>Pilots used multiple strategies to facilitate the integration of care. Network analyses identified 10 pilots that significantly improved either density or multiplexity of cross-sector ties, and one pilot with high cross-sector collaboration prior to WPC. Compared to pilots that did not improve cross-sector collaboration, these pilots meaningfully engaged partners in program design and implementation, used braided funds, and leveraged WPC to support broader systems change. These pilots also reported fewer challenges in developing and managing contractual relationships and ensuring meaningful use of data-sharing infrastructure by frontline staff responsible for care coordination.</p><p><strong>Conclusions: </strong>Data sharing is necessary but not sufficient for systems alignment. Collaboration strategies focused on addressing financial barriers to integration and strengthening normative and interpersonal integration are also needed.</p>","PeriodicalId":55065,"journal":{"name":"Health Services Research","volume":" ","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142781904","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Medicare at 60: Suggestions for balancing access to care and financial protections with fiscal concerns.","authors":"Michael E Chernew, Paul B Masi","doi":"10.1111/1475-6773.14415","DOIUrl":"https://doi.org/10.1111/1475-6773.14415","url":null,"abstract":"","PeriodicalId":55065,"journal":{"name":"Health Services Research","volume":" ","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142774932","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Long COVID and financial hardship: A disaggregated analysis at income and education levels.","authors":"Biplab Kumar Datta, Ishtiaque Fazlul, M Mahmud Khan","doi":"10.1111/1475-6773.14413","DOIUrl":"https://doi.org/10.1111/1475-6773.14413","url":null,"abstract":"<p><strong>Objectives: </strong>To examine how long COVID is associated with financial hardship (food insecurity, inability to pay bills, or threat of losing service) across income and education levels, and to assess the role of employment loss or reduced work hours in this hardship.</p><p><strong>Data source and study setting: </strong>We used nationally representative data on 271,076 adults from the 2022 Behavioral Risk Factor Surveillance System (BRFSS).</p><p><strong>Study design: </strong>We used multivariable binomial logistic regression models to estimate the average marginal effect of long COVID on financial hardships across multiple income and education groups.</p><p><strong>Principal findings: </strong>In general, we found a significant positive association between long COVID and the three measures of financial hardships across income and education groups (1-11 percentage points increase, 95% CI 0.00-0.02 and 0.07-0.14, respectively). Mediation analysis showed that lost or reduced hours of employment accounted for a significant portion (6%-20%) of the changes in financial distress.</p><p><strong>Conclusions: </strong>Long COVID has affected the economic wellbeing of people from all socioeconomic statuses, although at a higher rate for lower income groups. Policy attention is needed to address its economic impacts across income and education levels.</p>","PeriodicalId":55065,"journal":{"name":"Health Services Research","volume":" ","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142774931","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Drivers of infliximab biosimilar uptake: A comparative analysis of new biosimilar initiations versus switching in a national rheumatology registry.","authors":"Eric Thomas Roberts, Nick Bansback, Chien-Wen Tseng, Stephen Shiboski, Jing Li, Gabriela Schmajuk, Jinoos Yazdany","doi":"10.1111/1475-6773.14410","DOIUrl":"https://doi.org/10.1111/1475-6773.14410","url":null,"abstract":"<p><strong>Objective: </strong>To analyze the variability in new infliximab biosimilar starts as well as switching from bio-originator to biosimilar infliximab, across insurance payers and rheumatology practices nationally.</p><p><strong>Study setting and design: </strong>Data came from Rheumatology Informatics System for Effectiveness, a national registry with electronic health records from over 1100 US rheumatologists. Key outcomes include ever use of a biosimilar, date of initiation, and date of switching. Key variables of interest include insurance payer and practice.</p><p><strong>Data sources and analytic sample: </strong>Secondary analysis of 37,560 patients aged ≥18 years administered infliximab (bio-originator or biosimilar) between April 2016 and September 2022 in Rheumatology Informatics System for Effectiveness. We tested for differences in use of biosimilar infliximab by demographic characteristics, socioeconomic status, and diagnosis using standard mean differences and multivariable modified Poisson regression. We used generalized estimating equations to assess the adjusted effect of insurance and year of initiation on new biosimilar starts. We analyzed variation in biosimilar switching by insurance, date of switch, and practice.</p><p><strong>Principal findings: </strong>A total of 8196 (21.8%) infliximab users ever used a biosimilar and use did not differ significantly by demographic or clinical characteristics. In 2022, uptake among new users was higher among those with Medicaid (55%; 95%CI 43%-68%) and private insurance (51%; 95%CI 46%-57%) compared to Medicare (36%; 95%CI 29%-43%). Few prevalent bio-originator infliximab users switched to a biosimilar, and switching was lowest among Medicare beneficiaries (7% vs. 14.2% in Medicaid and 16.9% among privately insured). In adjusted analyses, practice level differences explained 37% of variation among new biosimilar starts and 34% of variation among those switching to a biosimilar.</p><p><strong>Conclusions: </strong>Our findings underscore two critical areas for enhancing biosimilar infliximab usage: increasing switching among prevalent users and increasing uptake among Medicare beneficiaries initiating treatment. Significant variation in uptake across practices also suggests that local switching policies are likely key drivers of uptake.</p>","PeriodicalId":55065,"journal":{"name":"Health Services Research","volume":" ","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142774930","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Instrumental variables in the cost of illness featuring type 2 diabetes.","authors":"Kyle Kole, Cathleen D Zick, Barbara B Brown, David S Curtis, Lori Kowaleski-Jones, Huong D Meeks, Ken R Smith","doi":"10.1111/1475-6773.14412","DOIUrl":"10.1111/1475-6773.14412","url":null,"abstract":"<p><strong>Objective: </strong>To ascertain how an instrumental variables (IV) model can improve upon the estimates obtained from traditional cost-of-illness (COI) models that treat health conditions as predetermined.</p><p><strong>Study setting and design: </strong>A simulation study based on observational data compares the coefficients and average marginal effects from an IV model to a traditional COI model when an unobservable confounder is introduced. The two approaches are then applied to real data, using a kinship-weighted family history as an instrument, and differences are interpreted within the context of the findings from the simulation study.</p><p><strong>Data sources and analytic sample: </strong>The case study utilizes secondary data on type 2 diabetes mellitus (T2DM) status to examine healthcare costs attributable to the disease. The data come from Utah residents born between 1950 and 1970 with medical insurance coverage whose demographic information is contained in the Utah Population Database. Those data are linked to insurance claims from Utah's All-Payer Claims Database for the analyses.</p><p><strong>Principal findings: </strong>The simulation confirms that estimated T2DM healthcare cost coefficients are biased when traditional COI models do not account for unobserved characteristics that influence both the risk of illness and healthcare costs. This bias can be corrected to a certain extent with instrumental variables. An IV model with a validated instrument estimates that 2014 costs for an individual age 45-64 with T2DM are 27% (95% CI: 2.9% to 51.9%) higher than those for an otherwise comparable individual who does not have T2DM.</p><p><strong>Conclusions: </strong>Researchers studying the COI for chronic diseases should assess the possibility that traditional estimates may be subject to bias because of unobserved characteristics. Doing so may be especially important for prevention and intervention studies that turn to COI studies to assess the cost savings associated with such initiatives.</p>","PeriodicalId":55065,"journal":{"name":"Health Services Research","volume":" ","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142717863","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}