Vitamin D intake among young Canadian adults: validation of a mobile vitamin D calculator app.

Objective: To establish the validity and reproducibility of the dietary component of a mobile vitamin D calculator app.
Methods: Participants entered their dietary intake into the Vitamin D Calculator app on 3 recording days over 1 month and underwent subsequent 24-hour dietary recalls.
Results: There were 50 adults (25 female), aged 18-25 years (mean, 22 ± 2 years). Paired-samples t tests tested for significant differences (P < .05) in mean vitamin D and calcium intake between the app and dietary recalls; Bland-Altman plots assessed agreement between the 2 measures. Intra-class correlations and Wilcoxon signed-rank tests assessed reproducibility of intakes estimated by the app. Mean vitamin D (n = 50) and calcium (n = 48) intakes and risk classifications did not differ significantly between the 2 measures (P > .05).
Conclusions and Implications: The Vitamin D Calculator app is a valid classification measure for dietary vitamin D and calcium intake. This tool could be used by the general public to increase awareness and intake of these nutrients.
(Copyright © 2015 Society for Nutrition Education and Behavior. Published by Elsevier Inc. All rights reserved.)