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Cited by 225Psychometric Methodologies and TestingAnxiety, Depression, Psychometrics, Treatment, Cognitive ProcessesMental Health Research Topics

The DOI matches its Crossref record; 33 of the 36 references it cites were found in a registry or an index.

Psychometric analysis of the Generalized Anxiety Disorder scale (GAD-7) in primary care using modern item response theory

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Jordan, Pascal, Shedden-Mora, Meike C., Löwe, Bernd·2017·PLOS ONE
DOI 10.1371/journal.pone.0182162PMC PMC5542568
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Abstract

OBJECTIVE: The Generalized Anxiety Disorder scale (GAD-7) is one of the most frequently used diagnostic self-report scales for screening, diagnosis and severity assessment of anxiety disorder. Its psychometric properties from the view of the Item Response Theory paradigm have rarely been investigated. We aimed to close this gap by analyzing the GAD-7 within a large sample of primary care patients with respect to its psychometric properties and its implications for scoring using Item Response Theory. METHODS: Robust, nonparametric statistics were used to check unidimensionality of the GAD-7. A graded response model was fitted using a Bayesian approach. The model fit was evaluated using posterior predictive p-values, item information functions were derived and optimal predictions of anxiety were calculated. RESULTS: The sample included N = 3404 primary care patients (60% female; mean age, 52,2; standard deviation 19.2) The analysis indicated no deviations of the GAD-7 scale from unidimensionality and a decent fit of a graded response model. The commonly suggested ultra-brief measure consisting of the first two items, the GAD-2, was supported by item information analysis. The first four items discriminated better than the last three items with respect to latent anxiety. CONCLUSION: The information provided by the first four items should be weighted more heavily. Moreover, estimates corresponding to low to moderate levels of anxiety show greater variability. The psychometric validity of the GAD-2 was supported by our analysis.

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Fig 1 Plots of the item information functions.
Fig 1 Plots of the item information functions.CC BY · PubMed Central
Fig 2 Test information curves for all two-item versions of the GAD-7.
Fig 2 Test information curves for all two-item versions of the GAD-7.CC BY · PubMed Central

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Metadata

Authors
Jordan, P., Shedden-Mora, M. C., & Löwe, B.
Affiliations
  • Universität Hamburg (DE)
  • Schön Klinik Hamburg Eilbek (DE)
Corresponding author
Jordan, Pascal
ORCID
Venue
PLOS ONE
Publisher
Public Library of Science (PLoS)
Published
2017-08-03
Volume
12
Issue
8
Pages
e0182162
ISSN
1932-6203 (ISSN-L)
DOI
10.1371/journal.pone.0182162
PMC
PMC5542568
OpenAlex
W2745129199
Cited by
225
References
36
Citations by year
2026: 13 · 2025: 25 · 2024: 29 · 2023: 35 · 2022: 31 · 2021: 37 · 2020: 31 · 2019: 14 · 2018: 9 · 2017: 1
FWCI
13.29
Type
journal article
Language
en
Open access
Licence
Locations
  • PLoS ONE (publishedVersion, cc-by)
  • PubMed Central (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • RePEc: Research Papers in Economics (submittedVersion)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
  • Figshare (submittedVersion, cc-by)
Funders
Bundesministerium für Bildung und Forschung (01KQ1002B)
Topics
  • Social Sciences › Decision Sciences › Management Science and Operations Research › Psychometric Methodologies and Testing
  • Social Sciences › Psychology › Experimental and Cognitive Psychology › Anxiety, Depression, Psychometrics, Treatment, Cognitive Processes
  • Social Sciences › Psychology › Experimental and Cognitive Psychology › Mental Health Research Topics
Keywords
Generalized Anxiety Disorder Scale, GAD-7, GAD-2, anxiety screening, item response theory, graded response model, unidimensionality, item information function, primary care patients, Bayesian item response theory, posterior predictive p-values, scale scoring
MeSH terms
Adolescent, Adult, Aged, Aged, 80 and over, Anxiety Disorders, Bayes Theorem, Female, Humans, Male, Markov Chains, Middle Aged, Primary Health Care, Psychiatric Status Rating Scales, Young Adult, Self Report

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