Adaptation and Validation of the Standardized Swallowing Assessment Tool for Patients With Moderate-Severe Traumatic Brain Injury and Cervical Spinal Cord Injury

Abstract

Oropharyngeal dysphagia is common in moderate-severe traumatic brain injury (TBI) and cervical spinal cord injury (SCI) patients and can have serious consequences. Delaying feeding in these patients can also be detrimental. Nonetheless, the psychometric properties of screening tools that can promptly identify dysphagia have never been tested in these neurotrauma populations. This study aimed to: (1) adapt, translate, and validate the content of the French-Canadian version of the the Standardized Swallowing Assessment (SSA) tool to meet the needs of moderate-severe TBI and cervical SCI patients, (2) examine its inter-rater reliability and criterion-concurrent validation, and (3) evaluate its clinical utility from the perspectives of critical care nurses. The SSA tool was adapted and translated using an integrated method for the cultural adaptation and translation of tools. Eleven experts participated in the adaptation of the SSA tool, which led to the clarification of one item, as well as a new step and instructions for the screening procedure. Content validation (i.e., item and scale relevance) was evaluated by multidisciplinary team members (n = 17). The mean content validity index (CVI) score was 0.97 for the entire scale, while the mean CVI scores for individual items ranged from 0.82 to 1.0. A total of 60 neurotrauma patients were enrolled for inter-rater reliability and criterion-concurrent validation. Interrater reliability was determined by comparing two scores: one score from nurses responsible for the care of enrolled patients and one score from the research nurse. The weighted kappa coefficients for inter-rater reliability were 0.86 for moderate-severe TBI patients (n = 30) and 0.73 for cervical SCI patients (n = 30). A speech language therapist (SLT) also assessed dysphagia and results were used as the standard clinical reference criterion to determine concurrent validity (sensibility and specificity) of the adapted SSA tool. The sensitivity and specificity were 92% and 50% for moderate-severe TBI, and 77% and 75% for cervical SCI, respectively. The positive predictive value (PPV) and the negative predictive value (NPV) were 65% and 87% in TBI patients, and 75% and 76% in SCI patients. Test accuracy was 71% and 77% for these same groups. The clinical utility of the tool was evaluated according to the following domains: appropriateness, accessibility of the required material, applicability, perceived effectiveness, and acceptability. Acceptability was the only domain with a level of agreement <80% (74%) among trauma critical care nurses (n = 49). Findings support the content validation and inter-rater reliability of the adapted French-Canadian version of the SSA tool in moderate-severe TBI and cervical SCI patients. Sensitivity was acceptable in both groups, but the specificity was lower, especially in moderate-severe TBI patients. Further validation of the adapted French-Canadian version of the SSA tool is needed in neurotrauma patients to confirm these results and to ensure safe dysphagia screening while avoiding oral feeding deferrals.

Keywords: dysphagia screening; traumatic brain injury; traumatic spinal cord injury; validation study.