Development and Validation of a Food Frequency Questionnaire to Assess Energy, Macronutrient and Micronutrient Intake of Adolescents Residing in Mumbai City

Abstract

Background: Assessment of dietary intake of adolescents is challenging due to irregular eating habits, socialdesirability bias, peer influence, and difficulty in estimating portion sizes. Validated dietary assessment toolsfor Indian adolescents are limited. We aimed to develop and validate a Semi-Quantitative Food FrequencyQuestionnaire (SQFFQ) to assess dietary energy and selected nutrient intake among adolescents in Mumbai city. Methods: The study was conducted in two phases. In Phase I, a 279-item SQFFQ was developed using literaturereview and a rapid online dietary survey. After content and face validity assessment, the questionnaire wasrefined to 104 food items across nine food groups. In Phase II, the tool was validated against 24-hour dietaryrecall method among 358 adolescents aged 10–19 years selected through random sampling. Nutrient intakes wereanalysed using DietCal software. Validity was assessed using advanced statistics. Reproducibility was tested in asubsample (n=44) using the test-retest method. Results: The SQFFQ showed significantly higher mean nutrient intakes than recalls (p<0.001), but demonstratedstrong correlations for crude and energy-adjusted nutrients (r=0.721–0.961, p<0.001). The cross-classificationanalysis showed that between 90.6% and 99.9% of foods were categorized into the same or adjacent quartiles,whereas gross misclassification remained below 10%. The Bland–Altman analysis indicated acceptable agreementbetween the methods. The reproducibility analysis showed high correlations (r=0.779–1.000), with good IntraclassCorrelation Coefficient and Cronbach’s alpha values. Conclusion: The developed SQFFQ was found to be a valid, reliable, practical, and cost-effective tool for assessingdietary intake of adolescents in Mumbai.