Academic Journal
Psychometric Validation of the Italian 8-Item Green Paranoid Thoughts Scale (GPTS-8).
| Τίτλος: | Psychometric Validation of the Italian 8-Item Green Paranoid Thoughts Scale (GPTS-8). |
|---|---|
| Συγγραφείς: | Preti A; Dipartimento di Neuroscienze 'Rita Levi Montalcini', Universita Degli Studi di Torino, Turin, Piedmont, Italy., Masala C; Dipartimento di Pedagogia Psicologia Filosofia, Universita Degli Studi di Cagliari, Cagliari, Sardinia, Italy., Petretto DR; Dipartimento di Pedagogia Psicologia Filosofia, Universita Degli Studi di Cagliari, Cagliari, Sardinia, Italy. |
| Πηγή: | International journal of methods in psychiatric research [Int J Methods Psychiatr Res] 2026 Dec; Vol. 35 (4), pp. e70097. |
| Τύπος έκδοσης: | Journal Article; Validation Study |
| Γλώσσα: | English |
| Στοιχεία περιοδικού: | Publisher: John Wiley & Sons Country of Publication: United States NLM ID: 9111433 Publication Model: Print Cited Medium: Internet ISSN: 1557-0657 (Electronic) Linking ISSN: 10498931 NLM ISO Abbreviation: Int J Methods Psychiatr Res Subsets: MEDLINE |
| Imprint Name(s): | Publication: Hoboken, NJ : John Wiley & Sons Original Publication: Chichester ; New York : Wiley, c1991- |
| Ιατρικοί όροι (MeSH): | Psychometrics*/instrumentation , Psychometrics*/standards , Paranoid Disorders*/diagnosis , Psychiatric Status Rating Scales*/standards, Humans ; Female ; Male ; Young Adult ; Reproducibility of Results ; Italy ; Adult ; Factor Analysis, Statistical ; Adolescent |
| Περίληψη: | Background: Paranoid ideation ranges from mild social-evaluative concerns to persecutory beliefs. The eight-item Green Paranoid Thoughts Scale (GPTS-8) provides a brief assessment of this continuum through reference and persecution items. Aims: To examine the psychometric properties of the Italian version of the GPTS-8, including its factorial structure, reliability, and convergent validity, in a non-clinical university sample. Methods: 243 university students completed the Italian GPTS-8 and the Prodromal Questionnaire-Brief (PQ-B). Confirmatory factor analyses compared unidimensional, two-factor, bifactor, and second-order models using maximum likelihood estimation with robust standard errors. Reliability was evaluated using Cronbach's α and McDonald's ω, and item-level contributions to the general factor were examined using bifactor indices (ECV, ωH, IECV). Results: The bifactor model showed the best fit, supporting a dominant general paranoia factor alongside specific reference and persecution dimensions. Internal consistency was good for the GPTS-8 total score (α = 0.78) and acceptable for the subscales (respectively, 0.68 and 0.66). Item-level diagnostics indicated that several items primarily reflected the general factor, consistent with a hierarchical organization of paranoid ideation. Item response patterns suggested greater sensitivity at moderate to higher levels of the latent trait. Participants scoring above established PQ-B thresholds showed significantly higher GPTS-8 scores across dimensions, supporting convergent validity. Conclusions: The Italian GPTS-8 showed satisfactory psychometric properties, providing incremental evidence for its structural validity in an Italian-speaking context. However, given the use of a convenience student sample, findings should be considered preliminary and not directly generalizable to broader or clinical populations. (© 2026 The Author(s). International Journal of Methods in Psychiatric Research published by John Wiley & Sons Ltd.) |
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| Contributed Indexing: | Keywords: bifactor analysis; confirmatory factor analysis; paranoia; persecution; self‐assessment |
| Entry Date(s): | Date Created: 20261001 Date Completed: 20261001 Latest Revision: 20261001 |
| Update Code: | 20261001 |
| DOI: | 10.1002/mpr.70097 |
| PMID: | 42817002 |
| Βάση Δεδομένων: | MEDLINE |
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