Usability of augmented-reality portion estimators during 24-hour dietary recall interviews

Abstract

Dietary recall instruments are structured interviews that capture information on foods and beverages consumed by participants in the past 24 hours. These instruments often rely on tools to help estimate portion size such as three-dimensional food models or two-dimensional images in a booklet or on a computer screen. Two-dimensional tools are good alternatives to bulky food models but may have scale challenges. To circumvent this issue, we developed and tested a digital portion estimator tool by rendering three-dimensional digital images in a tablet using augmented reality (AR) technology. The tablet was pilot tested during 24-hour dietary recall interviews with community-dwelling, English-speaking adult participants to determine its usability. We assessed whether tablet use influenced interview time, participant satisfaction, and whether it produced similar dietary intake data to interviews using food models or a booklet. Our results indicate comparable completion times and satisfaction scores across portion estimator tools. Average daily intake of food groups and nutrients were also similar, regardless of whether food was eaten in or away from home. While some participants desired more AR image stability and tablet durability, the technology offers an innovative method for examining life-size objects in a digital format during dietary recalls.