The Italian Version of the Illness Identity Questionnaire: A Preliminary Psychometric Validation in Adults with Chronic Illness

Authors

DOI:

https://doi.org/10.13129/2282-1619/mjcp-5427

Keywords:

Chronic illness, IIQ, Illness identity, Identity, Psychometric validation, Questionnaire

Abstract

Introduction: Illness identity, defined as the extent to which a chronic condition is integrated into one’s sense of self, is a key construct for psychological adjustment and quality of life. In the absence of validated instruments in Italian, this study aimed to translate, culturally adapt, and validate the Illness Identity Questionnaire (IIQ).

Methods: A cross-sectional study was conducted with 132 adults diagnosed with a chronic condition for at least six months. The factorial structure of the 25-item scale was examined using confirmatory factor analysis (CFA). Reliability (McDonald’s ω and Cronbach’s α) and construct validity were assessed through inter-factor correlations.

Results: CFA provided support for the original four-factor structure, showing overall acceptable but not optimal fit indices and adequate factor loadings. The alternative unidimensional model showed poor fit. Reliability ranged from satisfactory to excellent. Inter-factor correlations supported construct validity and were consistent with the theoretical model.

Conclusions: The study demonstrates promising preliminary psychometric properties of the Italian version of the IIQ and represents a useful tool for assessing adaptation to chronic illness.

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Published

15-08-2026

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Vol. 14 No. 2 (2026)

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