Psychometric Validation of the Italian 8-Item Green Paranoid Thoughts Scale (GPTS-8)

IF 3.4 3区医学 Q2 PSYCHIATRY

International Journal of Methods in Psychiatric Research Pub Date : 2026-09-30 DOI:10.1002/mpr.70097

Antonio Preti, Carmelo Masala, Donatella Rita Petretto

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引用次数: 0

Abstract

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.

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意大利八项绿色偏执思想量表（GPTS-8）的心理计量学验证

偏执思想的范围从轻微的社会评价关注到迫害信念。绿色偏执思维量表（GPTS-8）通过参考和迫害项目对这一连续体进行了简要评估。目的在非临床大学样本中检验意大利版GPTS-8的心理测量特性，包括其析因结构、信度和收敛效度。方法243名大学生填写意大利GPTS-8量表和前驱症状问卷（PQ-B）。验证性因子分析比较一维，双因素，双因素和二阶模型使用最大似然估计稳健的标准误差。采用Cronbach's α和McDonald's ω评价信度，采用双因子指标（ECV, ω h， IECV）检验项目水平对一般因子的贡献。结果双因子模型拟合最佳，支持一个显性的一般偏执狂因子以及特定的参考和迫害维度。GPTS-8总分的内部一致性良好（α = 0.78），子量表的内部一致性可接受（分别为0.68和0.66）。项目级诊断表明，有几个项目主要反映了一般因素，与偏执观念的分层组织相一致。项目反应模式表明，在中等到较高水平的潜在特质中，敏感性更高。得分高于既定PQ-B阈值的参与者在各维度上的GPTS-8得分显著较高，支持收敛效度。结论意大利语GPTS-8具有令人满意的心理测量特性，为其在意大利语语境中的结构效度提供了进一步的证据。然而，考虑到使用方便的学生样本，研究结果应被认为是初步的，不能直接推广到更广泛的或临床人群。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

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来源期刊

International Journal of Methods in Psychiatric Research 医学-精神病学

CiteScore

5.20

自引率

6.50%

发文量

审稿时长

>12 weeks

期刊介绍： The International Journal of Methods in Psychiatric Research (MPR) publishes high-standard original research of a technical, methodological, experimental and clinical nature, contributing to the theory, methodology, practice and evaluation of mental and behavioural disorders. The journal targets in particular detailed methodological and design papers from major national and international multicentre studies. There is a close working relationship with the US National Institute of Mental Health, the World Health Organisation (WHO) Diagnostic Instruments Committees, as well as several other European and international organisations. MPR aims to publish rapidly articles of highest methodological quality in such areas as epidemiology, biostatistics, generics, psychopharmacology, psychology and the neurosciences. Articles informing about innovative and critical methodological, statistical and clinical issues, including nosology, can be submitted as regular papers and brief reports. Reviews are only occasionally accepted. MPR seeks to monitor, discuss, influence and improve the standards of mental health and behavioral neuroscience research by providing a platform for rapid publication of outstanding contributions. As a quarterly journal MPR is a major source of information and ideas and is an important medium for students, clinicians and researchers in psychiatry, clinical psychology, epidemiology and the allied disciplines in the mental health field.