Technical Specifications for INDDEX24: New Dietary Assessment Technology for Scaling up Individual‐level Dietary Data in Low‐Income Countries
Authors: Coates Jennifer , Colaiezzi Brooke , Bell Winnie F.L. 
Published: November 2023

BackgroundLarge‐scale 24‐hour dietary recalls are infrequently conducted in low‐income countries. When conducted, dietary surveys generally rely on interviewer‐administered recalls using paper questionnaires. This approach is cumbersome, prone to error, and cost‐ and time‐prohibitive. As part of a multi‐year effort to scale up research architecture for dietary assessment in low‐income countries, the International Dietary Data Expansion (INDDEX) Project is investing in INDDEX24, a novel dietary assessment platform modeled on a 24‐hour dietary recall and targeted to users in low‐income countries. This study presents the process used to identify and refine the priority technical specifications for INDDEX24.MethodsA multi‐pronged approach was used to draft the technical specifications for the dietary assessment platform. First, an initial list of priority technical specifications was drafted by a dietary assessment expert with in‐depth knowledge and experience conducting dietary surveys in low‐income countries. Second, a systematic literature review of existing computer‐based 24‐hour recalls was completed, along with interviews with institutional representatives hosting these platforms. Third, members of the INDDEX Project's Technical Advisory Group (TAG) evaluated the appropriateness of the initial set of technical specifications in terms of their costs, benefits, and validity in the context of low‐income countries. Fourth, advice was sought from external technology experts on the feasibility of the technical specifications.ResultsThe technical specifications that emerged from this process included: 1) laptop or tablet based data collection, 2) use of the multiple‐pass approach, 3) interviewer administration format, 4) capable of contextual adaptability, 5) digital display of food photographs for food identification and portion size estimation, where feasible, 6) links to a changeable, contextually appropriate food composition database, 7) offline data collection capability, 8) scalable and appropriate for use during national surveys, 9) easy to use, and 10) low‐cost to adapt to varied cultural contexts. To meet the desired specifications the INDDEX24 platform design will include both a mobile application (app) for data collection and an integrated database website app. The database website app will have a universal structure to house context‐specific inputs required for processing 24‐hour recall data (e.g., food composition data). These databases will link to the INDDEX24 mobile app to enable real time processing of dietary data. It was decided that that further validation research in low‐income countries should be conducted to determine whether digital photographs could reliably be used as portion size estimation aids in low pictorial literacy contexts. The INDDEX Project intends to solicit additional design feedback from low‐income country end users as it develops INDDEX24.ConclusionThe evidence driven design, broad stakeholder contributions, and extensive testing of the prototype across a range of contexts will help ensure INDDEX24 is a high quality, transformative contribution to the field of dietary assessment in low‐income countries.Support or Funding InformationThis research was conducted as part of the International Dietary Data Expansion (INDDEX) Project, which is implemented by Tufts University's Gerald J. and Dorothy R. Friedman School of Nutrition Science and Policy with funding from the Bill & Melinda Gates Foundation.