My Meal Mate (MMM): Validation of the diet measures captured on a smartphone application to facilitate weight loss

Abstract

Accurate dietary assessment is an essential foundation of research in nutritional epidemiology. Due to the weaknesses in current methodology, attention is turning to strategies that automate the dietary assessment process to improve accuracy and reduce the costs and burden to participants and researchers. 'My Meal Mate' (MMM) is a smartphone application designed to support weight loss. The present study aimed to validate the diet measures recorded on MMM against a reference measure of 24Â h dietary recalls. A sample of fifty volunteers recorded their food and drink intake on MMM for 7Â d. During this period, they were contacted twice at random to conduct 24Â h telephone recalls. Daily totals for energy (kJ) and macronutrients recorded on MMM were compared against the corresponding day of recall using t tests for group means and Pearson's correlations. Bland-Altman analysis was used to assess the agreement between the methods. Energy (kJ) recorded on MMM correlated well with the recalls (day 1: r 0·77 (95Â % CI 0·62, 0·86), day 2: r 0·85 (95Â % CI 0·74, 0·91)) and had a small mean difference (day 1 (MMM -Â recall): -Â 68Â kJ/d (95Â % CI -Â 553, 418Â kJ) (Â -Â 16Â kcal/d, 95Â % CI -Â 127, 100Â kcal); day 2 (MMM -Â recall): -Â 441Â kJ/d (95Â % CI -Â 854, -Â 29Â kJ) (Â -Â 105Â kcal/d, 95Â % CI -Â 204, -Â 7Â kcal)). Bland-Altman analysis showed wide limits of agreement between the methods: -Â 3378 to 3243Â kJ/d (Â -Â 807 to 775Â kcal/d) on day 1. At the individual level, the limits of agreement between MMM and the 24Â h recall were wide; however, at the group level, MMM appears to have potential as a dietary assessment tool. Copyright © The Authors 2012.