{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T02:03:49Z","timestamp":1787018629158,"version":"build-2736575974"},"reference-count":27,"publisher":"SAGE Publications","license":[{"start":{"date-parts":[[2026,3,1]],"date-time":"2026-03-01T00:00:00Z","timestamp":1772323200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"},{"start":{"date-parts":[[2026,3,1]],"date-time":"2026-03-01T00:00:00Z","timestamp":1772323200000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/journals.sagepub.com\/page\/policies\/text-and-data-mining-license"}],"content-domain":{"domain":["journals.sagepub.com"],"crossmark-restriction":true},"short-container-title":["INQUIRY"],"published-print":{"date-parts":[[2026,3]]},"abstract":"<jats:p>\n                    The Affordable Care Act (ACA) allowed states to expand Medicaid eligibility, potentially improving access to care and reducing psychological distress among lower-income adults. However, evidence on population-level mental health effects remains mixed, and conventional two-way fixed-effects difference-in-differences (DiD) estimates can be biased under staggered adoption. This study estimates the effect of Medicaid expansion on frequent mental distress (FMD) among non-elderly adults, with emphasis on lower-income adults. We used Behavioral Risk Factor Surveillance System (BRFSS) data from 2011 to 2024 and restricted the sample to adults aged 18 to 64\u2009years. FMD was defined as \u226514\u2009days of poor mental health in the past 30\u2009days. Medicaid expansion was assigned by state implementation year. For transparent weighting and computational feasibility, we collapsed microdata to state-year prevalence using BRFSS survey weights and applied prespecified minimum cell-size and effective-sample screens (lower-income panel: unweighted N\u2009\u2265\u2009150 and Kish n_eff\u2009\u2265\u200950; pooled and higher-income panels: n_eff\u2009\u2265\u2009200). We estimated group-time average treatment effects using the Callaway\u2013Sant\u2019Anna staggered DiD framework (csdid), clustered standard errors at the state level, and used pair-balanced observations when panels were unbalanced. Income strata were defined using BRFSS household income categories (lower-income: inc_cat\u2009=\u20091; higher-income: inc_cat\u2009\u2208\u2009{7,8}) and are interpreted as economic-status proxies rather than Medicaid eligibility. In the lower-income state-year panel (353\u2009state-years), Medicaid expansion was not associated with a statistically significant change in FMD (ATT \u22120.0125; 95% CI \u22120.0521\u2009to\u20090.0271;\n                    <jats:italic toggle=\"yes\">P<\/jats:italic>\n                    \u2009=\u2009.54). Estimates in the higher-income (656 state-years) and pooled (709\u2009state-years) panels were similarly small and not statistically significant. Event-time estimates indicated modest heterogeneity at selected leads\/lags without a consistent post-expansion pattern. Medicaid expansion was not associated with significant reductions in population-level frequent mental distress during 2011 to 2024. Any mental health effects appear modest and heterogeneous across cohorts and follow-up periods, suggesting that insurance expansion alone may be insufficient to shift population psychological distress without complementary behavioral health capacity and upstream social supports.\n                  <\/jats:p>","DOI":"10.1177\/00469580261441768","type":"journal-article","created":{"date-parts":[[2026,4,13]],"date-time":"2026-04-13T14:08:50Z","timestamp":1776089330000},"update-policy":"https:\/\/doi.org\/10.1177\/sage-journals-update-policy","source":"Crossref","is-referenced-by-count":1,"title":["Medicaid Expansion and Frequent Mental Distress Among U.S. Adults: Staggered DiD Using BRFSS, 2011 to 2024"],"prefix":"10.1177","volume":"63","author":[{"ORCID":"https:\/\/orcid.org\/0009-0005-2436-3839","authenticated-orcid":false,"given":"Abimbola","family":"Adegoke","sequence":"first","affiliation":[{"name":"University of Texas Rio Grande Valley, Edinburg, USA"},{"name":"The University of Texas Health Science Center at Houston (UTHealth), TX, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0005-5615-1152","authenticated-orcid":false,"given":"Kola","family":"Adegoke","sequence":"additional","affiliation":[{"name":"University of Texas Rio Grande Valley, Edinburg, USA"},{"name":"New York Medical College, Valhalla, NY, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Olajide Alfred","family":"Durojaye","sequence":"additional","affiliation":[{"name":"Carleton Medical Clinic, AB, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0003-3953-3082","authenticated-orcid":false,"given":"Deborah","family":"Dawodu","sequence":"additional","affiliation":[{"name":"The University of Texas Health Science Center at Houston (UTHealth), TX, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-8071-5732","authenticated-orcid":false,"given":"Abiodun Isola","family":"Aluko","sequence":"additional","affiliation":[{"name":"CASA Mental Health (for Children &amp; Families in Alberta), Edmonton, AB, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0006-2435-2934","authenticated-orcid":false,"given":"Akorede","family":"Adekoya","sequence":"additional","affiliation":[{"name":"Fraser Health, Surrey, BC, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kenneth A.","family":"Knapp","sequence":"additional","affiliation":[{"name":"New York Medical College, Valhalla, NY, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"179","published-online":{"date-parts":[[2026,4,13]]},"reference":[{"key":"e_1_3_4_2_2","doi-asserted-by":"publisher","DOI":"10.1016\/S2215-0366(15)00505-2"},{"key":"e_1_3_4_3_2","doi-asserted-by":"publisher","DOI":"10.1007\/s40273-021-01019-4"},{"key":"e_1_3_4_4_2","doi-asserted-by":"publisher","DOI":"10.15585\/mmwr.mm6936a2"},{"key":"e_1_3_4_5_2","doi-asserted-by":"publisher","DOI":"10.1016\/S0140-6736(07)61602-X"},{"key":"e_1_3_4_6_2","unstructured":"Centers for Disease Control and Prevention. Behavioral Risk Factor Surveillance System (BRFSS): Overview\/FAQ; 2022. Accessed December 18 2025. https:\/\/www.cdc.gov\/brfss\/about\/brfss_faq.htm?"},{"key":"e_1_3_4_7_2","doi-asserted-by":"publisher","DOI":"10.1186\/s12874-016-0255-7Published"},{"key":"e_1_3_4_8_2","doi-asserted-by":"publisher","DOI":"10.1002\/bimj.19680100122"},{"key":"e_1_3_4_9_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.jeconom.2020.12.001"},{"key":"e_1_3_4_10_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.jeconom.2021.03.014"},{"key":"e_1_3_4_11_2","doi-asserted-by":"crossref","unstructured":"Rios-Avila F. csdid: difference-in-differences with multiple time periods in Stata [software]. GitHub repository (csdid_drdid); 2021. Accessed December 18 2025. https:\/\/www.stata.com\/meeting\/us21\/slides\/US21_SantAnna.pdf","DOI":"10.1177\/1536867X211000005"},{"key":"e_1_3_4_12_2","doi-asserted-by":"publisher","DOI":"10.1093\/restud\/rdad018"},{"key":"e_1_3_4_13_2","doi-asserted-by":"publisher","DOI":"10.1257\/aer.20181169"},{"key":"e_1_3_4_14_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.jeconom.2020.09.006"},{"key":"e_1_3_4_15_2","doi-asserted-by":"publisher","DOI":"10.1093\/restud\/rdae007"},{"key":"e_1_3_4_16_2","doi-asserted-by":"publisher","DOI":"10.1377\/hlthaff.2016.1650"},{"key":"e_1_3_4_17_2","doi-asserted-by":"publisher","DOI":"10.1001\/jamainternmed.2016.4419"},{"key":"e_1_3_4_18_2","doi-asserted-by":"publisher","DOI":"10.1093\/qje\/qjs020"},{"key":"e_1_3_4_19_2","unstructured":"Antonisse L Garfield R Rudowitz R Artiga S. The Effects of Medicaid Expansion Under the ACA: Updated Findings from a Literature Review. Kaiser Family Foundation; 2019. Accessed December 18 2025. https:\/\/digirepo.nlm.nih.gov\/master\/borndig\/101717180\/Issue-Brief-The-Effects-of-Medicaid-Expansion-Under-the-ACA-Updated-Findings-from-a-Literature-Review.pdf"},{"key":"e_1_3_4_20_2","doi-asserted-by":"publisher","DOI":"10.1002\/pam.21972"},{"key":"e_1_3_4_21_2","doi-asserted-by":"publisher","DOI":"10.1056\/NEJMsa1612890"},{"key":"e_1_3_4_22_2","doi-asserted-by":"publisher","DOI":"10.1111\/1475-6773.14625"},{"key":"e_1_3_4_23_2","doi-asserted-by":"publisher","DOI":"10.1002\/hec.4633"},{"key":"e_1_3_4_24_2","doi-asserted-by":"publisher","DOI":"10.1097\/MLR.0000000000001373"},{"key":"e_1_3_4_25_2","doi-asserted-by":"publisher","DOI":"10.1002\/hec.4256"},{"key":"e_1_3_4_26_2","doi-asserted-by":"publisher","DOI":"10.1176\/appi.ps.20220394"},{"key":"e_1_3_4_27_2","unstructured":"Hest R. Four Methods for Calculating Income as a Percent of the Federal Poverty Guideline (FPG) in the Behavioral Risk Factor Surveillance System (BRFSS). Robert Wood Johnson Foundation; 2019. Accessed February 12 2026. https:\/\/collections.nlm.nih.gov\/master\/borndig\/101753745\/Calculating_Income_as_PercentFPG_BRFSS.pdf"},{"key":"e_1_3_4_28_2","doi-asserted-by":"publisher","DOI":"10.1186\/1471-2288-13-49"}],"container-title":["INQUIRY: The Journal of Health Care Organization, Provision, and Financing"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/journals.sagepub.com\/doi\/pdf\/10.1177\/00469580261441768","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journals.sagepub.com\/doi\/full-xml\/10.1177\/00469580261441768","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journals.sagepub.com\/doi\/pdf\/10.1177\/00469580261441768","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,4,29]],"date-time":"2026-04-29T11:11:30Z","timestamp":1777461090000},"score":1,"resource":{"primary":{"URL":"https:\/\/journals.sagepub.com\/doi\/10.1177\/00469580261441768"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,3]]},"references-count":27,"alternative-id":["10.1177\/00469580261441768"],"URL":"https:\/\/doi.org\/10.1177\/00469580261441768","relation":{},"ISSN":["0046-9580","1945-7243"],"issn-type":[{"value":"0046-9580","type":"print"},{"value":"1945-7243","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,3]]},"article-number":"00469580261441768"}}