May I ask you a question? A large-scale experiment examining the effectiveness of a multimodal, conversational digital dietitian on nutritional knowledge in virtual reality

Dietitians play an essential role in health care, especially in curbing the obesity crisis, yet we will soon have a shortage of adequately trained professionals. To aid dietitians in reducing their workload while still offering personalised support to patients, we propose to introduce immersive digital dietitian assistants into the typical obesity care flow. During a session with the digital dietitian, patients learn about energy (calorie) density, portion sizes and the impact of food preparation methods. They practice these concepts by actively preparing virtual meals.
Our previous studies have shown that a single immersive session was equally effective as an in-person session in terms of portion size self-efficacy and led to improved portion size estimation. Still, we are exploring ways in which the effectiveness can be further improved. For example, one crucial difference between a session using our app and an analogous session with a physical dietitian, is that the patient is able to ask questions. Another difference is that a physical dietitian communicates through more than just words, including non-verbal cues such as gestures and facial expressions.
In this project, we aim to understand the influence of conversational capabilities and multimodal interaction with avatars on learning outcomes, in the context of nutrition education through an immersive digital dietitian.
While similar experiences are often tested at a small scale, with participants with a narrow or unrepresentative demographic, this project aims to test the effectiveness of the digital dietitian at a larger scale with the broader public.