Given the lack in a valid biomarker to assess dietary calcium intake (dCai), reproducible estimation of usual dCai is crucial for better understanding of its interaction with health outcomes in specific populations. This study tested the hypothesis that a calcium-focused food frequency questionnaire (FFQ) may be used to estimate dCai of women ≥50 years residing in a multicultural environment (Montreal, Canada). One hundred and eight women (age, 63.1±7.7 years; 98% postmenopausal) completed the FFQ twice and 4 nonconsecutive 24-hour recalls (24HRs) over 1 month. Medians of dCai were compared by Wilcoxon signed rank test. Reproducibility and relative validity of the FFQ were assessed by Spearman correlation (rs) and Cohen's weighted kappa (κw). Agreement was further assessed by cross-classification by quartiles, Bland-Altman plot, and sensitivity and specificity analyses. The median (interquartile range) dCai estimated by the FFQ and 24HRs were 723 (524-1033) mg/d and 854 (666-1068) mg/d, respectively (P