Dysphagia, or difficulty swallowing, is a common and often serious health concern that can lead to malnutrition, dehydration, and aspiration pneumonia. To systematically assess and track the severity of this condition, speech-language pathologists (SLPs) and other clinicians use the Dysphagia Outcome and Severity Scale (DOSS). The DOSS is a standardized, seven-point clinical tool that measures a patient’s functional swallowing ability based on objective assessment findings. This scale provides a common language for healthcare providers, allowing them to communicate patient status, monitor changes over time, and make informed decisions regarding diet and intervention strategies.
The Seven Levels of the DOSS Framework
The DOSS framework is an ordinal scale composed of seven distinct levels, ranging from the most severe impairment to completely normal function. This structure allows clinicians to categorize the degree of swallowing dysfunction based on a comprehensive evaluation of the patient’s swallowing mechanics. The core of the assessment focuses on three areas: how the food or liquid is handled in the mouth (oral stage bolus transfer), the amount of residue left in the throat (pharyngeal stage retention), and the effectiveness of airway protection against material entering the windpipe.
Level 1 represents the most severe dysphagia, indicating an inability to safely swallow any food or liquid orally. Conversely, Level 7 signifies normal swallowing function. The intermediate levels describe varying degrees of impairment, gradually moving from complete dependence on non-oral feeding to modified independence with a regular diet.
Translating Scores into Swallowing Function
A DOSS score translates directly into a patient’s real-world ability to eat and drink, guiding diet recommendations and the need for supervision. For example, a patient scoring Level 7 demonstrates normal swallowing in all situations, requires a regular diet, and needs no special strategies or extra time for meals. A slight step down to Level 6, described as “Within functional limits/modified independence,” means the patient still manages a normal diet, but may have a mild delay or residue that they clear spontaneously, possibly requiring some extra time to finish meals.
Significant functional differences appear between adjacent scores, particularly when comparing Level 5 and Level 3. A Level 5 patient exhibits mild dysphagia and may struggle only with thin liquids, potentially aspirating them, but they possess a strong, reflexive cough to completely clear their airway. This patient might need one diet consistency restricted and only distant supervision. In contrast, a Level 3 patient has moderate dysphagia, which often results in two or more diet consistencies being restricted.
This moderate impairment frequently requires total assistance or close supervision because the patient may aspirate two consistencies with a weak or nonexistent reflexive cough, or have airway penetration that they cannot clear spontaneously. A Level 2 rating indicates significant impairment where non-oral feeding is required, even if trace amounts of oral intake are used for pleasure or therapy.
DOSS and Treatment Planning
The DOSS score directly influences intervention and management decisions. It is used as an outcome measure to track progress, with the goal of therapy being to move the patient toward a higher, safer DOSS level. The initial score often determines the intensity and type of swallowing therapy, which may include direct techniques using food or indirect exercises to strengthen muscles.
The score is also directly linked to prescribing appropriate dietary modifications, often utilizing the International Dysphagia Diet Standardization Initiative (IDDSI) framework. For a patient with severe dysphagia (Level 1 or 2), the score confirms the need for non-oral nutrition, such as a feeding tube, to maintain adequate caloric and fluid intake. As swallowing function improves, a move from a score of 3 to 4, for instance, may warrant advancing the diet from a liquidized or pureed texture to a minced and moist texture, corresponding to specific IDDSI levels.
Changes in the DOSS score provide objective evidence for clinicians to justify advancing or restricting diet textures and reducing supervision. Clinicians monitor the patient’s DOSS score longitudinally to determine when a patient is ready to transition to a less restrictive diet or decrease the frequency of therapy sessions. This systematic approach ensures that treatment is responsive to the patient’s changing functional status, prioritizing both safety and quality of life.