Development and psychometric evaluation of the fear of medical imaging radiation scale (FOMIRS): insights from multimethod analysis

Insights Imaging. 2025 Jun 27;16(1):140. doi: 10.1186/s13244-025-02018-1.

Abstract

Objective: Fear of medical imaging radiation (FOMIR) may influence disease screening willingness; however, no validated tool currently exists to assess FOMIR. This study aimed to develop and validate the Fear of Medical Imaging Radiation Scale (FOMIRS) and explore its psychological mechanisms.

Methods: Based on classical test theory, the FOMIRS was developed through semi-structured interviews, grounded theory, and Delphi consultation. A cross-sectional survey with 1509 participants was conducted in Yunnan Province from September to December 2024. Psychometric properties were evaluated using construct validity, convergent validity, discriminant validity, criterion-related validity, content validity, and internal consistency. ROC curve analysis was used to determine the critical thresholds. Logistic regression analysis, network analysis, and structural equation modeling were employed to examine the relationships between the FOMIRS and related variables.

Results: The FOMIRS consisted of 18 items organized into a two-dimensional structure. It demonstrated good model fit (Goodness-of-fit index = 0.909, Comparative fit index = 0.949), convergent validity (AVE > 0.45, CR > 0.80), discriminant validity (HTMT = 0.574), criterion-related validity (γ = 0.441), and content validity (S-CVI = 0.889). The FOMIRS also showed excellent internal consistency (Cronbach's α = 0.926 and McDonald's ω = 0.935). Cost-induced refusal of imaging examinations, cancer screening willingness, online learning, imaging radiation cognition, and fear of cancer were identified as influencing factors of FOMIR (p < 0.05). FOMIR serves as a core node in the network, and imaging radiation cognition may affect cancer screening willingness through this mechanism (p < 0.05).

Conclusion: FOMIRS accurately measures individual FOMIR levels. It captures the psychological characteristics and behavioral tendencies associated with FOMIR and indicates potential mechanisms.

Critical relevance statement: We developed the Fear of Medical Imaging Radiation Scale (FOMIRS), a psychometric tool measuring individuals' fear of medical imaging radiation (FOMIR), demonstrating good reliability, validity, and practical application potential.

Key points: Evaluating individuals' FOMIR improves compliance with imaging exams and reduces related cognitive biases. FOMIRS is a reliable and valid tool for measuring FOMIR levels, capturing psychological and behavioral traits, and revealing interactions with external features. FOMIR is a complex phenomenon involving psychological traits, behavioral tendencies, and cognitive biases that affect people's willingness to undergo cancer screening.

Keywords: Fear of medical imaging radiation; Mechanisms; Reliability; Scale; Validity.