Questionnaire Validation

A bifactor structure fit the data better than a strictly unidimensional model. The 8-item CFA model performed better than the 20-item model on absolute fit indices. Internal consistency of the IQoL was high. Six rounds of exploratory factor analysis reduced the EPS from 32 content-valid items to a final 21-item structure. The overall EPS showed excellent internal consistency with Cronbach's alpha of 0.93. Exploratory factor analysis showed strong sampling adequacy and suitability for factor analysis. Convergent validity was supported by significant positive correlations between EPS and PEHB scores. Test-retest reliability is assessed using a subsample that repeats the SC-PC after four weeks. Bifactor reliability supported reporting a global IQoL score. All NP-SES-C items had acceptable item content validity index values. The three-factor exploratory model explained 78.608% of total variance. The final EFA model had KMO 0.91, significant Bartlett's test results, cumulative variance of 65.73%, and eigenvalues from 1.22 to 8.74. McDonald's omega was used as the primary model-based reliability estimate for the confirmatory stigma model. Content validity is evaluated by psycho-oncologi…