{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,25]],"date-time":"2026-09-25T23:14:20Z","timestamp":1790378060891,"version":"4.1.0"},"reference-count":56,"publisher":"Public Library of Science (PLoS)","issue":"10","license":[{"start":{"date-parts":[[2025,10,13]],"date-time":"2025-10-13T00:00:00Z","timestamp":1760313600000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Spanish Ministry of Universities","award":["FPU21\/998758"],"award-info":[{"award-number":["FPU21\/998758"]}]},{"name":"Spanish Ministry of Universities","award":["FPU23\/03224"],"award-info":[{"award-number":["FPU23\/03224"]}]}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"<jats:p>Ibogaine, an indole alkaloid derived from the root bark of <jats:italic>Tabernanthe iboga<\/jats:italic>, has long been used in traditional Bwiti healing rituals and shows promise for treating opioid dependence and neurological conditions, but existing psychometric tools fail to capture its distinctive subjective\/oneiric (dream-like) effects. To address this gap, we developed the 70-item Ibogaine Experience Scale (IES) through an iterative process informed by a prior qualitative study (n\u2009=\u200920) that identified eight experiential domains. A preliminary 144-item version was completed on site with a mobile device within 48 hours of treatment by 499 participants across two clinical settings\u2014cohort neuropsychiatric treatments (n\u2009=\u2009381) and substance use disorder treatments (n\u2009=\u2009118). We employed exploratory graph analysis, parallel analysis on polychoric correlations, and iterative item\u2010reduction (Gulliksen\u2019s Pool, MIREAL, MSA) to refine the scale. Semi-confirmatory factor analysis used Robust Unweighted Least Squares (RULS) with LOSEFER correction, oblimin rotation, and multiple fit indices (CFI, NNFI, GFI, AGFI, RMSR, WRMR). Cronbach\u2019s \u03b1, McDonald\u2019s \u03c9, H indices, EAP reliability, FDI, ORION, SR, and EPTD assessed internal consistency and factorial quality. The final structure comprises seven factors\u2014Narrative and symbolic visions; Visual changes; Discomfort and challenge; Cosmic\/Archetypal Visions; Introspection and personal transformation; Somatosensory hypersensitivity and physiological activation; Dissociation\u2014explaining 53.9% of variance, with excellent fit (CFI\u2009=\u2009.991; GFI\u2009=\u2009.983; RMSR\u2009=\u2009.041; WRMR\u2009=\u2009.038) and high internal consistency (\u03b1\u2009=\u2009.948; \u03c9\u2009=\u2009.946; subscale \u03c9\u2009=\u2009.65\u2013.91). Two subscales exhibited small gender effects. The IES provides a reliable, phenomenologically rich instrument for quantifying ibogaine\u2019s distinctive subjective effects. It supports research and clinical assessment by capturing the multidimensional, oneiric\/dream-like nature of the ibogaine experience. Future work should confirm this structure in independent, culturally diverse cohorts and explore predictive links between IES domains and therapeutic outcomes.<\/jats:p>","DOI":"10.1371\/journal.pone.0333296","type":"journal-article","created":{"date-parts":[[2025,10,13]],"date-time":"2025-10-13T17:23:09Z","timestamp":1760376189000},"page":"e0333296","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":1,"title":["The Ibogaine Experience Scale (IES): Development and psychometric properties of a multidimensional measure of ibogaine\u2019s subjective effects"],"prefix":"10.1371","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7377-1637","authenticated-orcid":true,"given":"Francisco","family":"Gonz\u00e1lez Espejito","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Laura","family":"Esteban 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