Repeatability of a Short Food Frequency Questionnaire to Assess Calcium Intake in Older Australians

Objective. To assess the repeatability of the validated Flinders Calcium Food Frequency Questionnaire (FFQ(CA)) for estimating dietary calcium intake in a sample of community dwelling older Australians. Methods. A test-retest repeatability study involving 100 subjects (≥65 years) living independently in metropolitan Adelaide, Australia. Estimates of daily calcium intake from the first (FFQ(CA1)) and repeated administration (FFQ(CA2)) were calculated from two versions (35-item and 15-item) of the FFQ(CA). The intraclass correlation coefficient (ICC) was used to assess the repeatability. Results. Moderate and comparable ICC values (r = 0.5, r = 0.6) were found across the two versions of the FFQ(CA). Conclusion. Both FFQ(CA) versions demonstrated moderate repeatability, supporting the results of previous studies.