Evidence map›Paper›PMID 39931546›Full record

ArticleFrontiers in neurology2025

Convergent construct validity and test-retest reliability of both German versions of the original and the revised Niigata PPPD Questionnaire: NPQ and NPQ-R.

Sarah Chételat, Eve-Yaël Gerber, Sarah El Khadlaoui, Frank Behrendt, Michaela Stark, Stefan Schädler, Maximilian Maywald, Lena Fabritius, Johannes Gerb, Denis Grabova and 8 more

Abstract read
In one paragraph

Article in Frontiers in neurology, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 2 papers.

0numbers the graph read from it
0cells of the map it votes in
2citing papers in PubMed
–field-weighted citation impact
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

The trial behind it

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3 · Its place in the literature

Who cites it

2 citing papers in PubMed.

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4 · The record

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PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

18 authors.

Sarah Chételat *School of Health Professions, Institute of Physiotherapy, Zurich University of Applied Sciences, Winterthur, Switzerland.
Eve-Yaël Gerber *Department of Research, Reha Rheinfelden, Rheinfelden, Switzerland.
Sarah El KhadlaouiGerman Center for Vertigo and Balance Disorders (DSGZ), University Hospital, LMU Munich, Munich, Germany.
Frank BehrendtDepartment of Research, Reha Rheinfelden, Rheinfelden, Switzerland.
Michaela StarkSchool of Health Professions, Institute of Physiotherapy, Zurich University of Applied Sciences, Winterthur, Switzerland.
Stefan SchädlerDepartment of Research, Reha Rheinfelden, Rheinfelden, Switzerland.
Maximilian MaywaldDepartment of Psychiatry and Psychotherapy, University Hospital, LMU Munich, Munich, Germany.
Lena FabritiusGerman Center for Vertigo and Balance Disorders (DSGZ), University Hospital, LMU Munich, Munich, Germany.
Johannes GerbGerman Center for Vertigo and Balance Disorders (DSGZ), University Hospital, LMU Munich, Munich, Germany.
Denis GrabovaGerman Center for Vertigo and Balance Disorders (DSGZ), University Hospital, LMU Munich, Munich, Germany.
Wiebke TrostDepartment of Research, Reha Rheinfelden, Rheinfelden, Switzerland.
Andreas ZwergalGerman Center for Vertigo and Balance Disorders (DSGZ), University Hospital, LMU Munich, Munich, Germany.
Ralf StroblGerman Center for Vertigo and Balance Disorders (DSGZ), University Hospital, LMU Munich, Munich, Germany.
Katrin ParmarDepartment of Research, Reha Rheinfelden, Rheinfelden, Switzerland.
Hans Ulrich GerthDepartment of Research, Reha Rheinfelden, Rheinfelden, Switzerland.
Leo H BonatiDepartment of Research, Reha Rheinfelden, Rheinfelden, Switzerland.
Sandra Becker-BenseGerman Center for Vertigo and Balance Disorders (DSGZ), University Hospital, LMU Munich, Munich, Germany.
Corina Schuster-AmftDepartment of Research, Reha Rheinfelden, Rheinfelden, Switzerland.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Background: Persistent Postural-Perceptual Dizziness (PPPD) is a frequent chronic functional disorder that manifests with dizziness, unsteadiness, or non-spinning vertigo present for at least 3 months. Characteristic provocation factors are moving or complex visual stimuli and exclusion of organic diseases. To assess the severity and impact of PPPD, Japanese researchers developed the Niigata PPPD Questionnaire (NPQ). The study's aim was to evaluate the concurrent construct validity and reliability [including test-retest reliability, internal consistency, standard error of measurement (SEM), and minimal detectable change (MDC)] of the German version of the NPQ (12 items) and its revised version, NPQ-R, which contains 19 items addressing additional symptoms and symptom behavior. Methods: The Swiss Reha Rheinfelden and the German Center for Vertigo and Balance Disorders included 265 PPPD patients (mean age 50.2 ± 16.8 years, disease duration 46.3 ± 76.6 months). Patients completed the NPQ and the NPQ-R (twice), the DHI and potentially related constructs: anxiety (ABC-Scale, VSS), depression (HADS), and general health (SF-36) once. To assess the questionnaires' reliability and validity, several statistical measures were calculated, including Spearman's rank correlation coefficients, Intraclass Correlation Coefficients (ICC Results: On average, patients scored 29.9 ± 13.2 for NPQ and 52.3 ± 19.6 for NPQ-R. Correlations between NPQ/NPQ-R and (1) disease-specific questionnaires were r Conclusion: The German versions of NPQ and NPQ-R are valid and reliable patient-reported outcome measures for assessing PPPD, demonstrating satisfactory psychometric measurement properties including convergent construct validity and reliability parameters: internal consistency, test-retest reliability, SEM, and MDC as an evaluative measure. The NPQ-R, with its additional subscales addressing associated symptoms and symptom behavior, represents both the patient and clinician perspective on PPPD-specific problems. Therefore, we recommend utilizing the NPQ-R for a comprehensive assessment of PPPD.

Indexed as

concurrent construct validityfunctional dizzinessinternal consistencyminimal detectable changepatient-reported outcome measurePersistent Postural-Perceptual Dizzinessstandard error of measurementtest-retest reliability

Identifiers

PMID39931546
PMCPMC11807810

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