Development and validation of semi-quantitative FFQ according to Türkiye Dietary Guideline

This study aims to develop and validate a semi-quantitative FFQ specifically designed to assess dietary intake among Turkish adults (19-64 years), based on the Türkiye Dietary Guideline (TDG-SFFQ). The primary goal is to evaluate the validity and reproducibility of the TDG-SFFQ to ensure it accurately captures habitual dietary patterns in the target population.

The TDG-SFFQ was administered through face-to-face interviews. Validity was assessed by comparing it with a 24-h dietary recall, while reliability was evaluated using a test-retest method after 4 weeks with fifty-six participants in Ankara, Türkiye. Daily intake means for energy, macronutrients and micronutrients obtained from both the TDG-SFFQ and 24-h dietary recall were calculated. Concordance between the two methods was analysed using the Pearson correlation coefficient and Bland-Altman plots.

Participants with adequate communication skills were recruited through digital announcements on social media and professional networks, followed by a snowball sampling method to expand the study reach. All eligibility screenings and subsequent data collection were conducted through face-to-face interviews.

The study group consisted of adults (n 420).

The agreement between the two methods demonstrated a statistically moderate or higher correlation for energy and macronutrients. Graphical representations for micronutrients also clustered around the mean, remaining within the 95 % CI. The reliability assessment of the TDG-SFFQ revealed strong linear correlations for energy and nutrients (p < 0·05), with intraclass correlation coefficients exceeding 0·666.

In summary, the TDG-SFFQ is a potentially valid and reliable tool for evaluating dietary intake in the Turkish adult population.