Conducting an accurate and timely assessment of dysphagia can improve the quality of life for those affected. But what are the most common diagnostic tests?

Dysphagia is a disorder that affects approximately 20% of the Italian population over the age of 50. In particular, significant swallowing difficulties are observed in people with Parkinson’s disease (50–90%), stroke survivors (40–80%), and people with multiple sclerosis (33–43%). In addition to these figures, there is a percentage of people who suffer from dysphagia but have not yet received a definitive diagnosis. We are talking about a percentage as high as 95%. For this reason, too, anaccurate and timely assessment of the disorder is essential, so that all possible measures can be taken to improve the quality of life for those affected. But how is dysphagia assessed? What are the most common diagnostic tests?

An important prerequisite for any dysphagia assessment test is the patient’s level of consciousness. If the patient is unresponsive or experiencing dyspnea, it is not possible to perform any swallowing tests. Furthermore, before proceeding to the actual tests, it is essential to collect data and conduct an interview with the patient as an integral part of the evaluation phase.

Once these preliminary evaluations have been completed, you can begin screening for dysphagia. The most common tests are as follows:

Gugging Swallowing Screen (GUSS)

This is an international clinical trial consisting of two phases:

• Indirect assessment of swallowing function
• Direct swallowing tests of semisolid, liquid, and solid substances.

Each patient examined receives a score (from 0 to 20) that determines the severity and category of their dysphagia.

Three-Ounce Water Swallow Test (WST, Smithard Test)

This dysphagia assessment test involves giving the patient 5 ml of room-temperature water with a spoon three times and, each time, verifying that the patient has swallowed it. If the patient experiences episodes of severe coughing or a gurgling voice, the test is suspended. In this case, a grade 4 (severe dysphagia) will be assigned. If, on the other hand, the patient does not cough, the test continues by offering the patient water directly from a glass; after a few seconds, the quality of their voice is assessed. If, even in this case, a hoarse and/or gurgling voice and coughing are observed, the patient is classified as Grade 3 (moderate dysphagia). If, on the other hand, only a hoarse and/or gurgling voice is observed, a grade 2 (mild dysphagia) is assigned. If the test is negative, a new test is performed, this time with 50 ml of water. If, even in this case, the patient shows no difficulty swallowing, a grade 1 (no dysphagia) can be confirmed. 

Finally, it is worth noting that there are two variants of this test: the pulse oximeter-sensitized WST and the auscultation-sensitized WST.

Bedside Swallowing Assessment

Much like the WST, this test involves giving the patient a teaspoon of water at room temperature. After 10–15 seconds, the examiner checks for any gurgling in the voice or episodes of coughing. If the patient responds positively, 50 ml of water is administered, and the examiner observes for signs of pharyngeal stagnation, coughing, or gurgling in the following minutes. Each observation is assigned a score that determines whether dysphagia is present. The Bedside Swallowing Assessment also includes the evaluation of parameters such as level of consciousness, head and trunk control, and respiration.

Daniels Test

This refers to a table listing the six symptoms of aspiration: dysphonia, dysarthria, voluntary cough, reduced post-swallow cough, altered or absent gag reflex, and changes in the voice after swallowing. A case of dysphagia is confirmed when at least two of these symptoms are present.