{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,20]],"date-time":"2026-08-20T15:08:45Z","timestamp":1787238525907,"version":"build-2736575974"},"reference-count":39,"publisher":"Oxford University Press (OUP)","issue":"4","license":[{"start":{"date-parts":[[2025,6,11]],"date-time":"2025-06-11T00:00:00Z","timestamp":1749600000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/academic.oup.com\/pages\/standard-publication-reuse-rights"}],"funder":[{"name":"National Health and Medical Research Council Partnership","award":["#APP1016326"],"award-info":[{"award-number":["#APP1016326"]}]},{"DOI":"10.13039\/501100001691","name":"Japan Society for the Promotion of Science","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100001691","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001691","name":"KAKENHI","doi-asserted-by":"publisher","award":["#24K02658"],"award-info":[{"award-number":["#24K02658"]}],"id":[{"id":"10.13039\/501100001691","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2025,6,11]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Dental caries is the most prevalent disease worldwide, associated with substantial health inequalities. Water fluoridation is a population strategy shown to effectively prevent dental caries; however, its impact on health inequalities remains inconclusive. We investigated the high-dimensional effect heterogeneity of water fluoridation in preventing dental caries among children in Australia.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>Data from the National Child Oral Health Study\u2014a national representative study conducted in 2012\u201314, linked to the information on lifetime exposure to fluoridated water\u2014were analysed (n\u2009=\u200917\u200a517 children aged 5\u201314\u00a0years). A doubly robust target minimum loss-based estimation was used to estimate the average treatment effect of lifetime exposure to fluoridated water (never exposed versus fully exposed) on the number of tooth surfaces with dental caries. The effect heterogeneity was evaluated by estimating the conditional average treatment effects (CATEs) using the causal forest algorithm, which integrated 47 child demographic, socioeconomic, and parental factors.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>In total, 58.1% were fully exposed to water fluoridation throughout their lifetime. Water fluoridation was associated with having \u20130.9 (95% confidence interval: \u20131.1, \u20130.8) fewer dental caries incidents. The estimated CATEs were mostly negative and the magnitude substantially varied (median CATE, \u20130.9; interquartile range, 0.7). Children from lower socioeconomic backgrounds exhibited greater benefits: i.e. the average CATEs ranged from \u20131.4 for children from a single parent with school-level education and low-income families to \u20130.8 for children from two parents with tertiary-level education and high-income families.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Water fluoridation was associated with lower dental caries and exhibited greater benefits for vulnerable subpopulations.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1093\/ije\/dyaf080","type":"journal-article","created":{"date-parts":[[2025,5,16]],"date-time":"2025-05-16T08:07:30Z","timestamp":1747382850000},"source":"Crossref","is-referenced-by-count":7,"title":["Water fluoridation as a population strategy for reducing oral health inequalities: high-dimensional effect heterogeneity analysis using machine learning"],"prefix":"10.1093","volume":"54","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6114-5604","authenticated-orcid":false,"given":"Yusuke","family":"Matsuyama","sequence":"first","affiliation":[{"name":"Department of Dental Public Health, Graduate School of Medical and Dental Sciences, Institute of Science Tokyo , Bunkyo, Tokyo,","place":["Japan"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Diep H","family":"Ha","sequence":"additional","affiliation":[{"name":"School of Dentistry, The University of Queensland , Brisbane, Queensland,","place":["Australia"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sakura","family":"Kiuchi","sequence":"additional","affiliation":[{"name":"Department of Dental Public Health, Graduate School of Medical and Dental Sciences, Institute of Science Tokyo , Bunkyo, Tokyo,","place":["Japan"]},{"name":"School of Dentistry, The University of Queensland , Brisbane, Queensland,","place":["Australia"]},{"name":"Frontier Research Institute for Interdisciplinary Sciences, Tohoku University , Sendai, Miyagi,","place":["Japan"]},{"name":"Department of International and Community Oral Health, Tohoku University Graduate School of Dentistry , Sendai, Miyagi,","place":["Japan"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrew J","family":"Spencer","sequence":"additional","affiliation":[{"name":"Australian Research Centre for Population Oral Health, University of Adelaide , Adelaide, South Australia,","place":["Australia"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8405-9872","authenticated-orcid":false,"given":"Jun","family":"Aida","sequence":"additional","affiliation":[{"name":"Department of Dental Public Health, Graduate School of Medical and Dental Sciences, Institute of Science Tokyo , Bunkyo, Tokyo,","place":["Japan"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Loc G","family":"Do","sequence":"additional","affiliation":[{"name":"School of Dentistry, The University of Queensland , Brisbane, Queensland,","place":["Australia"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"286","published-online":{"date-parts":[[2025,7,1]]},"reference":[{"key":"2025070110012638100_dyaf080-B1","doi-asserted-by":"crossref","first-page":"427","DOI":"10.1093\/ije\/30.3.427","article-title":"Sick Individuals and Sick Populations","volume":"30","author":"Rose","year":"2001","journal-title":"Int J Epidemiol"},{"key":"2025070110012638100_dyaf080-B2","doi-asserted-by":"crossref","first-page":"216","DOI":"10.2105\/AJPH.2007.114777","article-title":"Transcending the known in public health practice: The inequality paradox: the population approach and vulnerable populations","volume":"98","author":"Frohlich","year":"2008","journal-title":"Am J Public 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