{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,23]],"date-time":"2026-10-23T20:08:46Z","timestamp":1792786126228,"version":"4.5.0"},"reference-count":25,"publisher":"Oxford University Press (OUP)","issue":"5","license":[{"start":{"date-parts":[[2026,7,22]],"date-time":"2026-07-22T00:00:00Z","timestamp":1784678400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Institute of Dermatology","id":[{"id":"https:\/\/ror.org\/02j6cz137","id-type":"ROR","asserted-by":"crossref"}]},{"name":"Department of Medical Services"},{"DOI":"10.13039\/501100004397","name":"Ministry of Public Health, Thailand","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100004397","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,9,30]]},"abstract":"Abstract<\/jats:title>\n \n Background<\/jats:title>\n Ultraviolet (UV) phototherapy is a cost-effective, guideline-recommended treatment for moderate-to-severe psoriasis, supported by extensive evidence demonstrating its long-term safety and clinical efficacy. As a foundational therapeutic option in routine dermatological practice, access to phototherapy contributes meaningfully to sustained disease control and overall patient outcomes. Nevertheless, comprehensive nationwide data describing real-world utilization, particularly within universal health coverage systems, remain limited. A clearer understanding of patterns of access may therefore offer valuable insight into the organization and delivery of dermatological care.<\/jats:p>\n <\/jats:sec>\n \n Objectives<\/jats:title>\n To quantify socioeconomic and regional inequality in UV phototherapy utilization and identify determinants of access within a universal health coverage system.<\/jats:p>\n <\/jats:sec>\n \n Methods<\/jats:title>\n This nationwide cross-sectional study (January\u2013December 2023) integrated individual-level administrative health insurance data with a facility-based survey conducted across Thailand\u2019s 13 health regions to assess the availability of dermatologists and UV phototherapy devices. Patients with psoriasis (N = 49 219) were identified using International Classification of Diseases (ICD)-10 codes L40.0\u2013L40.9. Moderate-to-severe disease (n = 16 188) was defined using treatment-based proxies, including receipt of phototherapy, systemic agents or biologic therapies identified through ICD-9 procedure codes and Thai Medicine Terminology drug codes. The primary outcome was phototherapy utilization. Multivariable logistic regression was applied to estimate adjusted odds ratios. Socioeconomic inequality was quantified using the Concentration Index and concentration curves.<\/jats:p>\n <\/jats:sec>\n \n Results<\/jats:title>\n Among 49 219 identified patients with psoriasis (202 776 encounters), 16 188 were classified as having moderate-to-\u00adsevere disease. Of these, only 3.3% received UV phototherapy. Utilization was concentrated in higher-income provinces, as reflected by a positive Concentration Index of 0.213. In multivariable analysis, access to phototherapy was independently associated with age, psoriasis subtype, insurance scheme, geographical region, provincial income level, and the availability of dermatologists and phototherapy devices.<\/jats:p>\n <\/jats:sec>\n \n Conclusions<\/jats:title>\n Access to phototherapy in Thailand remains limited and unequally distributed despite universal insurance coverage. Reducing disparities in workforce distribution and service capacity may enhance equitable access to this core dermatological treatment modality and support more equitable long-term disease control in routine clinical practice.<\/jats:p>\n <\/jats:sec>","DOI":"10.1093\/skinhd\/vzag110","type":"journal-article","created":{"date-parts":[[2026,7,22]],"date-time":"2026-07-22T15:00:57Z","timestamp":1784732457000},"page":"785-792","source":"Crossref","is-referenced-by-count":0,"title":["Inequality and determinants of access to phototherapy among patients with psoriasis in Thailand"],"prefix":"10.1093","volume":"6","author":[{"given":"Chutima","family":"Churee","sequence":"first","affiliation":[{"name":"Photodermatology Division, Institute of Dermatology,\u00a0Department of Medical Services, Ministry of Public Health , Bangkok ,","place":["Thailand"]},{"name":"Department of Preventive and Social Medicine, Faculty of Medicine, Chulalongkorn University , Bangkok 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