Evidence map›Paper›PMID 42899365›Full record

ArticleEuropean journal of neurology2026

A Data-Driven Operational Definition of Square-Wave Jerks and Its Diagnostic Utility in Progressive Supranuclear Palsy.

Duy Duan Nguyen, Andrea Quattrone, Mark Paine, Amir Fazlollahi, Soohyun Lee, Baibin Ben Wang, Tanya Davidson, Felicia Coleman, John D O'Sullivan, Peter J Nestor

Abstract read
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Article in European journal of neurology, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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1 · What the graph read from it

What it found

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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

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3 · Its place in the literature

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4 · The record

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5 · Who and what money

Authors and funding

10 authors.

Duy Duan NguyenClem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, St Lucia, Queensland, Australia.ORCID https://orcid.org/0000-0002-4773-1471
Andrea QuattroneNeuroscience Research Centre, University Magna Graecia of Catanzaro, Catanzaro, Italy.ORCID https://orcid.org/0000-0003-2071-2083
Mark PaineNeuro-Ophthalmology and Neuro-Otology Clinic, Department of Neurology, Royal Brisbane & Women's Hospital, Herston, Queensland, Australia.
Amir FazlollahiClem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, St Lucia, Queensland, Australia.
Soohyun LeeClem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, St Lucia, Queensland, Australia.
Baibin Ben WangClem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, St Lucia, Queensland, Australia.ORCID https://orcid.org/0009-0000-7992-3403
Tanya DavidsonCognitive Health Program, Mater Research Institute, The University of Queensland, South Brisbane, Queensland, Australia.
Felicia ColemanClem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, St Lucia, Queensland, Australia.
John D O'SullivanDepartment of Neurology, Royal Brisbane & Women's Hospital, Herston, Queensland, Australia.ORCID https://orcid.org/0000-0003-0422-8590
Peter J NestorClem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, St Lucia, Queensland, Australia.ORCID https://orcid.org/0000-0002-5860-5921

Funding

Mater FoundationNational Health and Medical Research Council 2023/GNT2030157
6 · The paper itself

Abstract

backgroundThe Movement Disorder Society diagnostic criteria for progressive supranuclear palsy (PSP) list frequent square-wave jerks (SWJ) as a suggestive oculomotor feature. A standardised operational definition of SWJ is however presently lacking.

objectiveTo create a data-driven optimal SWJ definition and to assess its diagnostic utility in PSP.

methodsWe prospectively recruited PSP n = 25, Parkinson's disease (PD) n = 32, Alzheimer's disease (AD) n = 35, and controls n = 88. SWJ were recorded with a visual fixation task using video-oculography. Multiple candidate definitions of SWJ were generated by systematically varying morphological features, producing 32 candidate definitions. A nested cross-validation was used to obtain unbiased diagnostic performance and optimised SWJ definition. Results were then externally tested in a fully independent sample of n = 25 PSP, n = 41 PD and n = 25 controls.

resultsThe optimal selected SWJ definition consisted of saccade amplitude 1°-8°, intra-SWJ intervals 20-600 ms, directional opposition within ±45°, and amplitude similarity ≤ 0.25. Only SWJ rate, and not morphological features, was distinctive for PSP. SWJ rate gave out-of-fold AUCs of 0.81 for PSP versus controls, 0.71 for PSP versus AD, 0.63 for PSP versus PD, and 0.76 for PSP versus all non-PSP groups. Post hoc analyses using this data-driven definition on the external validation cohort yielded relatively comparable results. SWJ rate > 24/min had high specificity, but low sensitivity, for PSP when compared with PD.

conclusionsSWJ rate was significantly increased in PSP but with insufficient discriminant ability for use as a stand-alone diagnostic marker. This data-driven definition may serve as a reproducible operational definition for future research.

Indexed as

Supranuclear Palsy, ProgressiveAgedAged, 80 and overAlzheimer DiseaseFemaleHumansMaleMiddle AgedParkinson DiseaseProspective StudiesSaccadesatypical parkinsonismfixationsnested cross‐validationParkinson's diseaseprogressive supranuclear palsy

Identifiers

PMID42899365
PMCPMC13681254

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.