{
  "abstract": "BackgroundFluctuations in pain intensity are intrinsic to non-specific chronic low back pain (nsCLBP). Nevertheless, pain fluctuations have rarely been considered when investigating pathophysiological mechanisms. Therefore, a novel study protocol was developed and implemented to systematically assess the impact of fluctuating pain states on pain-related measures.\n\nMethodsThe final study cohort consisted of 45 nsCLBP patients and 47 age- and sex-matched healthy controls (HCs). Patients participated in three visits, conducted during different pain states (i.e. clinically relevant pain, low-intensity clinical pain / pain-free, clinically irrelevant pain induced using a Qutenza 8% capsaicin patch). Pain fluctuations were monitored through online assessments every four days and guided the pseudorandomized visit scheduling. HCs participated in a single visit. Each study visit comprised a multimodal battery of pain-related measures.\n\nResults93.33% of patients completed all three visit types in a pseudorandomized order ({chi}{superscript 2}=1.50, p=0.826). Visit scheduling was possible due to the high self-report adherence (median=93.48%), unrelated to self-report burden ({rho}=-0.097, p=0.53). Study visits were conducted during different pain states, as indicated by: i) the significantly higher low back pain intensity in the clinically relevant pain visit (mean[SD]: 3.98[0.90]), compared to the low-intensity clinical pain (1.03[0.86]) and clinically irrelevant pain (1.13[0.82]) visits (p-values<0.001), as well as by ii) the successful induction of a moderate-to-high clinically irrelevant pain across assessments.\n\nConclusionDespite scheduling complexity and pain state transition uncertainty, a pain state-dependent pseudorandomized study design is feasible and could improve the understanding of nsCLBP mechanisms.",
  "abstract_shown": true,
  "affiliations": [
    "Integrative Spinal Research, Department of Chiropractic Medicine, Balgrist University Hospital, University of Zurich, Zurich, Switzerland; Neuroscience Center Z"
  ],
  "article_type": "PUBLISHAHEADOFPRINT",
  "arxiv": null,
  "author_total": 10,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "B. Chozas Barrientos"
    },
    {
      "name": "M. Hau"
    },
    {
      "name": "L. Sirucek"
    },
    {
      "name": "A. Langenfeld"
    },
    {
      "name": "M. Wehrli"
    },
    {
      "name": "B. Wirth"
    },
    {
      "name": "N. Zoelch"
    },
    {
      "name": "J. Devan"
    },
    {
      "name": "S. Dudli"
    },
    {
      "name": "P. Schweinhardt"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/c162q2ya3pkdw.bib",
  "cited_by": 0,
  "doi": "10.64898/2026.08.26.26359760",
  "fulltext_url": "https://www.medrxiv.org/content/10.64898/2026.08.26.26359760v1.full",
  "id": "c162q2ya3pkdw",
  "issns": [],
  "landing_url": "https://www.medrxiv.org/content/10.64898/2026.08.26.26359760v1",
  "language": null,
  "licence": "CC-BY",
  "licence_label": "CC BY",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "medrxiv",
      "pain medicine"
    ],
    [
      "openalex",
      "2736|Musculoskeletal pain and rehabilitation"
    ]
  ],
  "openalex": "W7204800514",
  "pdf_url": "https://www.medrxiv.org/content/10.64898/2026.08.26.26359760v1.full.pdf",
  "pmcid": null,
  "pmid": null,
  "published": "2026-08-26",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/c162q2ya3pkdw.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:17:25Z",
      "native_id": "10.64898/2026.08.26.26359760",
      "source": "medrxiv",
      "url": "https://www.medrxiv.org/content/10.64898/2026.08.26.26359760v1"
    }
  ],
  "subjects": [
    {
      "field": "medicine",
      "origin": "medrxiv:pain medicine",
      "subfield": "surgery"
    }
  ],
  "title": "Pain state-dependent multimodal assessment in non-specific low back pain: a pseudorandomized study design with implementation insights",
  "title_text": "Pain state-dependent multimodal assessment in non-specific low back pain: a pseudorandomized study design with implementation insights",
  "type": "preprint",
  "updated_at": "2026-10-30T12:17:42Z",
  "url": "https://research.draconitic.com/paper/c162q2ya3pkdw",
  "venue": "medRxiv",
  "versions": []
}