Validation of a New Food Frequency Questionnaire for Protein Intake Assessment in Korean

BACKGROUND: Protein intake is a modifiable factor associated with sarcopenia prevention; however, no appropriate methods exist to assess dietary protein intake in Koreans. This study developed and validated a simple and convenient food frequency questionnaire (FFQ) to determine protein intake in Koreans. METHODS: A total of 120 participants aged >19 years were asked to complete both the FFQ used by the Korean National Health and Nutrition Examination Survey (KNHANES) and the newly developed Korean Protein Assessment Tool (KPAT). Protein intakes measured using the FFQ and the KPAT were compared using Pearson correlation coefficients, Bland-Altman plots, and intraclass correlation coefficients. RESULTS: Protein intakes from the FFQ (62.06±25.56 g/day) and KPAT (61.12±24.26 g/day) did not differ significantly (P=0.144). Pearson’s correlation coefficient values ranging from 0.92 to 0.96 indicated a positive correlation, while the intraclass correlation coefficient of 0.979 indicated excellent reliability in protein intake of the FFQ and the KPAT. The Bland-Altman plot also showed high agreement in the mean differences in protein intakes estimated by the FFQ and the KPAT. CONCLUSIONS: KPAT, a newly developed and simplified method, showed an acceptable correlation compared to previous FFQ tools. Thus, the KPAT may be useful to assess dietary protein intake in the Korean population.