{
  "abstract": "This study aimed to develop a Japanese version of the Sleep Problem Acceptance Questionnaire (SPAQ-J) and assess its reliability and validity. The SPAQ-J was developed through a forward-backward translation procedure with permission from the original authors. The sample included 861 adults with insomnia who completed questionnaires on experiential avoidance, insomnia symptoms, dysfunctional beliefs about sleep, sleep-related safety behaviors, insomnia catastrophizing, and pre-sleep arousal. Confirmatory factor analysis confirmed that the SPAQ-J retained the two-factor structure of the original version (CFI = 0.972, TLI = 0.958, RMSEA = 0.082, SRMR = 0.059): Activity Engagement and Willingness. Although internal consistency was adequate (Activity Engagement: α = 0.868, ω = 0.870; Willingness: α = 0.895, ω = 0.895), test-retest reliability was below the recommended threshold (Activity Engagement: ICC = 0.586, Willingness: ICC = 0.589). In terms of construct validity, Willingness moderately correlated with all scales, whereas Activity Engagement showed moderate-to-weak correlations. Hierarchical multiple regression analysis revealed that adding the SPAQ-J subscales significantly enhanced the explanatory power. Measurement invariance analysis across sex and age groups showed no significant changes in the fit indices, indicating stability. These findings suggest that the SPAQ-J is a valid and partially reliable measure of psychological flexibility related to sleep problems in the Japanese population.",
  "abstract_shown": true,
  "affiliations": [
    "Graduate School of Humanities and Life Sciences, Tokyo Kasei University, Tokyo, Japan",
    "Graduate School of Humanities, Kwansei Gakuin University, Nishinomiya, Japan",
    "School of Humanities, Kwansei Gakuin University, Nishinomiya, Japan",
    "Behavioral Sleep Medicine and Sciences Laboratory, Department of Psychological Counseling, Faculty of Humanities, Tokyo Kasei University, Tokyo, Japan"
  ],
  "article_type": "Research Article",
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  "author_total": 4,
  "authors": [
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      "name": "Mizuki Bando"
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      "name": "Tomohiro Asakura"
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      ],
      "name": "Hiroshi Sato"
    },
    {
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        3
      ],
      "name": "Isa Okajima"
    }
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  "doi": "10.1371/journal.pone.0358990",
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  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "journal",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
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  "native_subjects": [
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  "pdf_url": "https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0358990&type=printable",
  "pmcid": null,
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  "published": "2026-10-16",
  "publisher": "Public Library of Science",
  "ris": "https://research.draconitic.com/paper/f3r8vg8rqh9aw.ris",
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    {
      "first_seen": "2026-10-30T12:17:23Z",
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      "origin": "plos:statistical methods",
      "subfield": "statistics"
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      "origin": "plos:clinical psychology",
      "subfield": "psychiatry"
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  "title": "Reliability and validity of the Japanese version of the Sleep Problem Acceptance Questionnaire",
  "title_text": "Reliability and validity of the Japanese version of the Sleep Problem Acceptance Questionnaire",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T12:17:23Z",
  "url": "https://research.draconitic.com/paper/f3r8vg8rqh9aw",
  "venue": "PLOS One",
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}