The Initiative is a small research collaboration. The staff below participate across publications, methodology briefs, and dataset construction; external collaborators are listed by name on the publications they contribute to.
Director
Helena Weiss directs the Dietary Assessment Initiative. Her research focuses on the validation of digital dietary assessment methods and the comparative epidemiology of self-reported intake instruments. She holds a PhD in Nutritional Epidemiology and an MPH in Biostatistics, and is a Registered Dietitian.
Areas: Dietary assessment validation; Nutritional epidemiology; Bland-Altman methodology; Bias in self-reported intake · ORCID: 0000-0002-4517-8829
Senior Researcher, Biostatistics
Daniel Okafor leads the Initiative's statistical methods program. His work centers on agreement statistics for dietary assessment (limits of agreement, intraclass correlation, equivalence testing) and on the design of validation studies for image-based food recognition. PhD in Biostatistics; MS in Nutritional Sciences.
Areas: Agreement statistics; Bland-Altman analysis; Equivalence testing; Sample size methodology · ORCID: 0000-0001-7263-4419
Senior Researcher, Computational Methods
Meera Patel's research sits between food science and computer vision. She studies how image-based dietary assessment systems handle portion ambiguity, mixed dishes, and cuisine distribution shift, and how those failure modes interact with downstream calorie and macronutrient estimation. PhD in Food Science with a minor in Computer Science.
Areas: Image-based dietary assessment; Portion estimation; Cuisine-level evaluation; Computer vision for food · ORCID: 0000-0003-1148-6602
Research Associate
Sofia Rivera coordinates the Initiative's reference-meal protocols and weighed-food data collection. Her background combines clinical dietetics with nutritional epidemiology field methods, and she contributes to the Initiative's methodology briefs on USDA FoodData Central usage and on portion-estimation protocols.
Areas: Weighed-food protocols; USDA FoodData Central; Field data collection; Clinical dietetics · ORCID: 0000-0002-9956-3074
Methods Lead, Epidemiology
Lars Henriksen leads the Initiative's epidemiologic methods strand, with a focus on bias structures in self-reported and AI-mediated dietary intake data and on systematic-review methodology for digital health applications. PhD in Epidemiology; prior faculty appointments in nutritional epidemiology.
Areas: Systematic review methodology; Measurement error; Self-report bias; Digital health epidemiology · ORCID: 0000-0002-2051-7733