Introduction: Validation of a culturally specific FFQ is important in assessing habitual dietary intake of ethnic population groups. This study aimed to assess the validity and reproducibility of a FFQ developed specifically for determining the dietary intake of Malaysian Punjabis.
Methods: Subjects were approached through voluntary participation for the development and validation phase in the Klang Valley. A list of foods consumed by participants (n=100) was documented through a 3-day dietary recall. The validation process was conducted by verifying the developed FFQ against another group of Punjabi adult volunteers (n=101) who kept a 2-day dietary record. Macronutrients, dietary fibre, fatty acids, cholesterol, three types of minerals (calcium, sodium, iron) and four vitamins (B12, folate, C, A) were included in the analysis. Reproducibility was shown with intraclass correlation (ICC) values between FFQ1 vs FFQ2 that were administered 6 months apart among 32 participants.
Results: In the validation study, the FFQ1 was found to have over-estimated almost all nutrients compared to those in the dietary records. The Spearman correlation coefficients for energy, carbohydrate, protein and fat intake based on the FFQ1 and 2-day dietary records were 0.54, 0.38, 0.47, and 0.31, respectively. The classification into the same and adjacent quartiles was between 61- 84% for the nutrients consumed. Bland Altman plots showed relatively good agreement (between ±2 standard deviation) for both the dietary methods used. Reproducibility analysis of ICC (FFQ1 vs FFQ2) was between 0.46-0.76 for macronutrients and 0.20-0.92 for micronutrients.
Conclusion: The developed FFQ could be used as a valid tool for assessing dietary intake of Malaysian Punjabis, as it showed a moderate agreement with dietary record for intake of energy and macronutrients.