ABSTRACT
Background/Objectives
The increasing use of dietary supplements in Türkiye underscores the need for validated instruments to assess dietitians’ knowledge, attitudes and self-efficacy regarding supplements. However, no validated Turkish tool is currently available. This study aimed to culturally adapt the Dietitians’ Survey of Comfort, Opinions and Preparedness in Education in Supplements (-SCOPE) Questionnaire into Turkish (Diyetisyenlerin Eğitim, Supleman Tercihleri ve Konforu Anketi; DESTEK) and evaluate its psychometric properties.
Methods
This methodological study included 223 dietitians. Exploratory factor analysis (Principal Axis Factoring with Direct Oblimin rotation) was conducted to identify the underlying structure, followed by confirmatory factor analysis to test model fit. Internal consistency was assessed using Cronbach’s alpha. Convergent validity was examined through composite reliability and average variance extracted, and discriminant validity was evaluated using the Fornell–Larcker criterion.
Results
A four-factor structure explaining 38.3% of total variance was identified. Sampling adequacy was acceptable (KMO = 0.78; Bartlett’s test: χ2(153) = 1023.27, p < 0.001). Confirmatory factor analysis demonstrated acceptable model fit (CFI = 0.915; TLI = 0.893; RMSEA = 0.062; SRMR = 0.057). The total scale showed acceptable internal consistency (α = 0.795), with subscale α values ranging from 0.531 to 0.824. Composite reliability values ranged from 0.60 to 0.83. Test–retest analysis demonstrated acceptable temporal stability (overall ICC = 0.772). Discriminant validity was supported.
Conclusions
The findings provide preliminary evidence supporting the validity and reliability of the DESTEK scale for assessing Turkish dietitians’ knowledge, attitudes and perceived preparedness regarding dietary supplements. Given its multidimensional structure, DESTEK may be useful for evaluating specific domains of supplement-related competence; however, further validation in larger and more diverse samples is recommended.
Journal of Human Nutrition and Dietetics, Volume 39, Issue 5, October 2026. Read More