{
  "abstract": "ObjectiveRegression-based normative approaches are widely used in neuropsychology but often rely on score transformations to satisfy model assumptions. We compared previously published linear regression (LR)-based norms with norms derived using Generalized Additive Models for Location, Scale and Shape (GAMLSS) for the brief cognitive battery used in the Norwegian Dementia Disease Initiation (DDI) cohort.\n\nMethodGAMLSS norms were developed using the same normative samples as the original LR norms for the Consortium to Establish a Registry for Alzheimers Disease (CERAD) word list test, Trail Making Test (TMT) A and B, FAS phonemic fluency, and Visual Object and Space Perception Battery (VOSP) Silhouettes. Expected low-score frequencies and empirical base rates were assessed in a normative subsample (n = 131). Clinical implications were evaluated in the DDI clinical cohort (n = 643) using Mild Cognitive Impairment (MCI) classification, two-year diagnostic stability and change, and cerebrospinal fluid (CSF) biomarkers.\n\nResultsCompared with LR norms, GAMLSS yielded lower frequencies of low scores, primarily driven by CERAD delayed recall. Nevertheless, concordance between approaches was high ({kappa} = 0.91), with only 4.2% discordant classifications. Two-year diagnostic stability and change were broadly similar across approaches, and CSF biomarker profiles did not clearly favor either normative method.\n\nConclusionsGAMLSS provided a more faithful representation of neuropsychological score distributions, particularly for bounded and non-normal outcomes. However, downstream clinical differences were modest in this setting, suggesting that well-calibrated LR norms may remain robust for clinical classification.",
  "abstract_shown": true,
  "affiliations": [
    "The Arctic University of Norway, Tromso, Norway"
  ],
  "article_type": "PUBLISHAHEADOFPRINT",
  "arxiv": null,
  "author_total": 11,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "B.-E. Kirsebom"
    },
    {
      "name": "I. Myrvoll Lorentzen"
    },
    {
      "name": "J. Espenes"
    },
    {
      "name": "I. Vollo Eliassen"
    },
    {
      "name": "F. Gonzalez-Ortiz"
    },
    {
      "name": "A. Wallin"
    },
    {
      "name": "K. Waterloo"
    },
    {
      "name": "M. Eckerstrom"
    },
    {
      "name": "G. Rolfseng Grontvedt"
    },
    {
      "name": "E. Hessen"
    },
    {
      "name": "T. Fladby"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/2wy46j8mn8129.bib",
  "cited_by": 0,
  "doi": "10.64898/2026.09.01.26361590",
  "fulltext_url": "https://www.medrxiv.org/content/10.64898/2026.09.01.26361590v1.full",
  "id": "2wy46j8mn8129",
  "issns": [],
  "landing_url": "https://www.medrxiv.org/content/10.64898/2026.09.01.26361590v1",
  "language": null,
  "licence": "CC-BY-NC-ND",
  "licence_label": "CC BY-NC-ND",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by-nc-nd/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "medrxiv",
      "psychiatry and clinical psychology"
    ],
    [
      "openalex",
      "2738|Dementia and Cognitive Impairment Research"
    ]
  ],
  "openalex": "W7208761111",
  "pdf_url": "https://www.medrxiv.org/content/10.64898/2026.09.01.26361590v1.full.pdf",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-01",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/2wy46j8mn8129.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:17:47Z",
      "native_id": "10.64898/2026.09.01.26361590",
      "source": "medrxiv",
      "url": "https://www.medrxiv.org/content/10.64898/2026.09.01.26361590v1"
    }
  ],
  "subjects": [
    {
      "field": "medicine",
      "origin": "medrxiv:psychiatry and clinical psychology",
      "subfield": "psychiatry"
    }
  ],
  "title": "Smooth Curves, Similar Conclusions? Comparing Linear Regression and GAMLSS Neuropsychological Norms",
  "title_text": "Smooth Curves, Similar Conclusions? Comparing Linear Regression and GAMLSS Neuropsychological Norms",
  "type": "preprint",
  "updated_at": "2026-10-30T12:17:47Z",
  "url": "https://research.draconitic.com/paper/2wy46j8mn8129",
  "venue": "medRxiv",
  "versions": []
}