Item-level content validity ratios all exceeded 0.83, and the scale-level content validity index reached 0.90, indicating strong expert agreement on the relevance of the items. Exploratory factor analysis was used to derive the underlying structure, which was then evaluated with ordinal confirmatory factor analysis in the same sample. Removing two items produced a 16-item questionnaire organized into three factors: First Aid Willingness, Negative Emotions, and Perceived Knowledge.

The three-factor model showed acceptable fit to the data, with a comparative fit index of 0.95, a Tucker–Lewis index of 0.94, a root mean square error of approximation of 0.06 (90% confidence interval 0.05 to 0.07), and a standardized root mean square residual of 0.06, although the scaled chi-square statistic of 288.09 with 101 degrees of freedom remained statistically significant. Composite reliability ranged from 0.79 to 0.90 across the factors, Cronbach’s alpha from 0.72 to 0.87, and McDonald’s omega from 0.74 to 0.87. Average variance extracted ranged from 0.49 to 0.59, with convergent validity for the Negative Emotions factor described as borderline, while discriminant validity was supported.

Measurement invariance testing showed that configural, threshold, metric, and scalar invariance held across gender, grade level, and perceived family income, meaning the questionnaire functions comparably across these groups for subscale interpretation and latent mean comparisons within the study sample. Strict invariance was supported across grade level and perceived family income but not across gender, so stricter forms of comparison involving equal item residuals are not justified for gender groups in this data.

The authors characterize the findings as preliminary evidence for the Turkish version’s psychometric properties. Because the validation was conducted in a single sample, independent replication is needed, along with evaluation of the questionnaire’s temporal stability, responsiveness to change over time, and external validity against other measures or outcomes. The results support use of the adapted instrument for assessing first-aid willingness among Turkish adolescents in the studied context, but generalization beyond this population awaits further testing.

Subject of Research: Cross-cultural adaptation and psychometric validation of the First Aid Willingness Questionnaire among Turkish adolescents

Article Title: Cross-cultural adaptation, validation, and measurement invariance of the First Aid Willingness Questionnaire (FAWQ) among Turkish adolescents

Article References: Özbey, H., Çalışır, Ö., Bayat, M., Beşiktaş, S., & Roba, A. A. (2026). Cross-cultural adaptation, validation, and measurement invariance of the First Aid Willingness Questionnaire (FAWQ) among Turkish adolescents. PLOS One, 21(10), e0361329. https://doi.org/10.1371/journal.pone.0361329

Image Credits: AI Generated

DOI: 10.1371/journal.pone.0361329

Keywords: first aid, adolescents, questionnaire validation, psychometrics, measurement invariance, confirmatory factor analysis, Turkish students, school health, Cross-cultural, adaptation, validation, measurement