{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,21]],"date-time":"2026-01-21T07:20:32Z","timestamp":1768980032198,"version":"3.49.0"},"reference-count":39,"publisher":"Public Library of Science (PLoS)","issue":"1","license":[{"start":{"date-parts":[[2026,1,20]],"date-time":"2026-01-20T00:00:00Z","timestamp":1768867200000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000061","name":"Fogarty International Center","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100000061","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100009633","name":"Eunice Kennedy Shriver National Institute of Child Health & Human Development","doi-asserted-by":"crossref","id":[{"id":"10.13039\/100009633","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/100000026","name":"the National Institute on Drug Abuse","doi-asserted-by":"crossref","id":[{"id":"10.13039\/100000026","id-type":"DOI","asserted-by":"crossref"}]},{"name":"the National Institute of Mental Health of the National Institutes of Health","award":["D43 TW011548"],"award-info":[{"award-number":["D43 TW011548"]}]}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"<jats:sec id=\"sec001\">\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Contingency management (CM) effectively enhances adherence and retention in methadone maintenance treatment (MMT). But implementing CM in resource-limited settings is challenging, particularly due to costs associated with providing incentives. In this study, we aimed to describe and quantify patient preferences regarding low-cost CM incentives to promote adherence and retention in MMT.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec002\">\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>We conducted a cross-sectional survey using a best-worst scale (case 1) among 216 participants ages 18 or older undergoing MMT in six clinics in Hanoi, Vietnam. The study asked participants to complete 13 sets of best-worst scaling tasks. Each task presented a subset of four incentives chosen from a total of 13 incentives. Net scores for each incentive were calculated by subtracting the total times an incentive was rated as least appealing from the total times it was rated as most appealing. Standardized scores were derived by dividing the net score by the sum of selections and then converted to weighted probabilities (WP) that ranged from 0% to 100% (example interpretation: an incentive with WP of 20% is twice as desired as an incentive with WP of 10%). The 95% confidence intervals (95% CI) were estimated using bootstrapping.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec003\">\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>The mean age of participants was 44.7 (SD\u2009=\u20098.0, range: 25\u201366). Most were male (95%), married (59%), and had not completed high school (69%). About half (50%) had been on methadone treatment for more than five years. The most preferred incentives were \u201cdiscount for monthly methadone fees\u201d (WP\u2009=\u200916.9, 95% CI: 16.0, 17.8) and \u201ctake-home methadone privileges\u201d (WP\u2009=\u200911.3, 95% CI: 10.1, 12.6), followed by \u201cpriority coupons for early medical examinations\/consultations\u201d. In contrast, the least preferred incentives were \u201cbeing recognized\/praised in their community\u201d (WP\u2009=\u20094.5, 95% CI: 4.0, 5.0) and \u201cbeing recognized\/praised at their clinic\u201d (WP\u2009=\u20094.7, 95% CI: 4.1, 5.4).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec004\">\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>Treatment fee support, take-home methadone privilege, and coupons for prioritizing checkup at clinics emerged as the most desirable incentives for patients. We recommend future CM intervention may consider using these incentives as the first-line rewards to offer to reinforce treatment adherence and retention in methadone treatment. These findings suggest potential low-cost CM strategies that could inform decision-making in MMT programs.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1371\/journal.pone.0341359","type":"journal-article","created":{"date-parts":[[2026,1,20]],"date-time":"2026-01-20T18:39:11Z","timestamp":1768934351000},"page":"e0341359","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":0,"title":["Patient preferences for incentives in Contingency Management interventions in methadone treatment: A best-worst scale analysis"],"prefix":"10.1371","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2633-110X","authenticated-orcid":true,"given":"Thuy Thi Dieu","family":"Dao","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hue Thi","family":"Nguyen","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3261-2098","authenticated-orcid":true,"given":"Trang Thu","family":"Nguyen","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Thuyet Thi","family":"Phung","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5913-612X","authenticated-orcid":true,"given":"Van Hai","family":"Hoang","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Huong Thi","family":"Le","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Brian W.","family":"Pence","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Giang Minh","family":"Le","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Vivian F.","family":"Go","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1934-7827","authenticated-orcid":true,"given":"William C.","family":"Miller","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"340","published-online":{"date-parts":[[2026,1,20]]},"reference":[{"key":"pone.0341359.ref001","article-title":"Prevalence and shared risk factors of HIV in three key populations in Vietnam: A systematic review and meta-analysis","volume":"151","author":"P Lee","year":"2023","journal-title":"Epidemiol Infect"},{"key":"pone.0341359.ref002","unstructured":"UNAIDS. 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