Diagnostic Validity of Clinical Observations for Detecting Physiologic Swallowing Impairment

A clinical swallow evaluation (CSE) is a noninvasive and indirect assessment of the anatomical and physiological integrity of the swallowing mechanism in a natural setting. A CSE goes beyond a screening, a dichotomized indicator of dysphagia risk, by comprehensively examining the patient's swallowing through gaining sensory and motor information of oral and pharyngeal function. Information obtained from CSEs in combination with medical, social, and environmental patient related factors allow clinicians to make critical decisions about patients' health and quality of life. It is essential that we have assessment tools with rigorous methodological quality to optimize the accuracy of our clinical judgement. The purpose of this study is to investigate the diagnostic validity of clinical observations obtained through the Mann Assessment of Swallowing Ability (MASA) to better inform clinicians regarding the confidence that the items are testing what they are intended to test and reflect indication of true physiologic swallowing impairment and airway invasion. Area Under the ROC Curve (AUC) analyses revealed that the MASA's diagnostic validity showed acceptable accuracy levels for detecting oral impairment and aspiration, and poor accuracy for detecting pharyngeal impairment and penetration. In the cross-validation analysis, the AUC accuracy level for aspiration changed from acceptable to poor, but remained the same for oral impairment, pharyngeal impairment and penetration. In our sample, acceptable levels for detecting aspiration but poor levels for detecting pharyngeal impairment indicate that the MASA does an adequate job of identifying risk but not explaining the nature of impairment. These results support the need for videofluoroscopic imaging to identify the nature and severity of swallowing impairment, guide intervention and provide recommendations for safe and efficient oral intake.