VALIDITY AND RELIABILITY OF THE FOOD FREQUENCY QUESTIONNAIRE TO ASSESS FOOD GROUPS INTAKE AMONG ADULTS IN QATAR

Background: Qatar's National Vision 2030 (QNV 2030) emphasizes promoting healthier lifestyles and reducing non-communicable diseases, requiring precise dietary assessment tools. Previous Food Frequency Questionnaire (FFQ) used in Qatar was adapted from the U.S. Diet History Questionnaire rather than developed from local dietary data. This study developed and validated a culturally adapted FFQ based on Qatar Biobank dietary data, reflecting Qatari and expatriate diets. Methods: A cross-sectional validation was conducted among 121 adults (mean age 36.0±11.6 years; 74 females, 47 males), including Qatari citizens and expatriate residents who have lived in Qatar for more than 5 years. Ethical approval was obtained from Qatar University’s Institutional Review Board (IRB 084/2024-EA). The 97-item FFQ, covering 16 food groups, was validated against three non-consecutive 24-hour recalls (24-HR). The FFQ was administered twice, one month apart. Validity and reliability were assessed using Spearman correlations, cross-classification, and Bland–Altman analyses. Results: Energy-adjusted Spearman correlations for major food groups ranged from r = 0.30 to 0.62 (p < 0.001), with the strongest correlations for meat (r = 0.62), fruits (r = 0.53), vegetables (r = 0.50), and dairy (r = 0.48). Arabic sweets and cooking oils showed poor validity (p > 0.05). Cross-classification indicated 52–88% agreement in the same or adjacent quartiles. Test–retest reliability ranged from moderate to excellent for most food groups (r = 0.47–0.82), with correlations exceeding 0.70 for meat, staples, dairy, and fats/oils (p < 0.001). Agreement between the FFQ administrations exceeded 85% for most food groups. The FFQ overestimated dairy, staples, and fruits while underestimating vegetables. Conclusions: This culturally adapted FFQ demonstrates acceptable validity and good reliability for ranking individuals by food group intake, suitable for diet-disease research and public health policy aligned with Qatar National Vision 2030.