Evaluating Oral Phase Function in Adult Dysphagia: Characteristics and Measurement Elements of Assessment Tools

The oral phase is the critical initial stage of swallowing, where the oral motor function is essential.Oral phase impairment can lead to severe complications such as malnutrition and pneumonia.Therefore, accurate assessments are clinically critical.This study systematically reviewed the characteristics and measurement elements of assessment tools for evaluating the oral function and oral motor function in adult dysphagia patients.A systematic literature search was conducted using PubMed, CINAHL, Google Scholar, and RISS databases for articles published up to June 2025.Ultimately, 43 articles were selected, and 22 standardized assessment tools identified within these studies were analyzed.The assessments were classified into standardized clinical tools (n=22) and instrument-based methods.An analysis of the standardized tools revealed a frequent focus on static measures like 'Anterior spillage' (54.5%) and 'mealtime duration' (45.5%), while dynamic aspects like 'tongue propulsion' (9.1%) were overlooked.The instrument-based methods, including oral diadochokinesis, chewing gum tests, and tongue pressure measurement, had the advantage of quantitatively evaluating the oral function.The results showed that an integrated and standardized assessment protocol capable of deeply evaluating the oral phase is needed.This study provides foundational data for the evidence-based application of oral phase assessments in future clinical practice and research.(