Food Classification for Swallowing Disorders Perception by Senior Population

Texture-modified diets (TMDs) contain safe foods for individuals with dysphagia, such as soft solids or thick liquids. Considering the large population affected by dysphagia, especially older adults, it is essential to accurately measure the physical properties of these foods. The rheological and textural characteristics defined in major dysphagia guidelines-IDDSI, BDA, and the Smile Care System-are based on the experience and perception of health experts, but it is mostly unknown to which physical parameter corresponds to the classification. It is also uncertain whether older adults with dysphagia, who are the primary users of these guidelines, fully understand the classification levels and safety recommendations. This study aimed to (i) identify discrepancies between instrumental measurements and human-based classification systems, and (ii) understand the difficulties encountered when the elderly population attempts to follow this dietary guideline. To investigate this, classical tests (Texture Profile Analysis and viscosity at 50s^-1), a new imitative IDDSI method, and participants' food classifications according to IDDSI, BDA, and the Smile Care System were registered. Results showed that imitative IDDSI methods often classify foods at higher IDDSI levels than participants for semi-solid foods with high viscosity. Among participants, there were disagreements for foods of intermediate or ambiguous textures, and they claimed the systems to be too technical and had unclear or confusing information, and suggested ways to improve it, such as guiding material, simple language, or food comparison.