Relationship between IDDSI Flow Test and Consistometric Measures for Consistency Classification - An Examination of Thickened Liquids Prepared Using Starch-Based and Xanthan Gum-Based Thickening Agents.

Introduction: Consistency of liquid food plays an important role in managing patients with dysphagia, which can be objectively evaluated by using IDDSI Flow Test and consistometry. The present study established the relationship between IDDSI Flow Test and consistometric measures, and examined the measurement limitations of each test associated with thickened liquids prepared using starch-based and xanthan gum-based thickening agents.

Methods: Thirteen thickened liquid samples of consistency ranging from IDDSI Level 1 (mildly thick) to Level 3 (moderately thick) were prepared using starch-based and xanthan gum-based thickeners. IDDSI Flow Test and consistometric measures were obtained and analyzed using correlation and regression.

Results: A strong correlation was observed between both tests. Regression analyses revealed a linear and a quadratic relationship between IDDSI Flow Test and consistometric measurements, respectively.

Conclusion: Starch-based and xanthan gum-based thickeners exhibited different relationships between IDDSI Flow Test and consistometric measurements. Findings allow easy conversion and adaptation of consistometric measures to the IDDSI framework, which renders the use of consistometry in the clinical settings as a complementary quantitative measurement of liquid consistency to IDDSI Flow Test.