Part 2: Implementing Internal and External Evidence
We began our discussion on employing evidence-based practice (EBP) in swallowing rehabilitation during the spring newsletter, with careful consideration for upholding ethics in treatment and focusing on patient perspective. Let’s continue by delving deeper into incorporation of evidence in dysphagia therapy. ASHA defines the implementation of evidence as “The best available information gathered from the scientific literature (external evidence) and from data and observations collected on your individual client (internal evidence).” ASHA’s recommended EBP process includes the following steps: Frame the clinical question, gather evidence, assess the evidence, and make the clinical decision (ASHA 2020).
As we frame the clinical question, we begin with review of the pertinent diagnoses and characteristics of the patient, along with the selection of applicable assessment tools. During the clinical swallow evaluation (CSE), selection of a standardized and validated measure with adequate sensitivity and specificity is crucial. Sensitivity refers to the ability of a test to designate an individual with disease as positive. A highly sensitive test means there are few false negative results, and thus fewer cases of disease missed. Specificity of a test is its ability to designate an individual who does not have a disease as negative (McCollough, 2002).
If our CSE indicates presence of dysphagia or aspiration, we will move forward with gathering additional evidence during an instrumental swallow study. During the FEES or VFSS, we not only are able to confirm presence of dysphagia and/or aspiration, but can identify the specific physiological impairments and introduce respective compensatory and treatment techniques. This may include postural changes, swallowing maneuvers, and/or modifying bolus properties. Utilizing these patient-specific interventions for internal evidence collection during assessment sets the stage for carry over into an effective EBP treatment plan (Logemann, 2011).
Our assessment of the external collection of evidence should include a search of the best available and current research, pertinent to the patient’s specific physiological impairments, with respect for principles of neuroplasticity and exercise science. It is important to employ critical appraisal when reviewing literature, as a multitude of study designs exist. Designs are categorized into primary and secondary research. Primary research pertains to individual studies attempting to answer a specific research question using raw data. Secondary research combines the findings from primary research studies to provide conclusions about that body of evidence.
Under primary research, the experimental study designs, specifically randomly controlled trials (RCTs), are highly valued because they minimize threats to internal validity and allow researchers to show causation between the intervention and observed changes. Keeping this in mind however, the standing literature most suitable for your patient may very well be comprised of a different design (Drisko, et al., 2019). Other types of primary research include case studies and observational/non-experimental designs; whereas those under secondary research include systematic reviews, meta-analyses, and clinical guidelines.
Additionally, we find in the literature the principles of neuroplasticity contribute to EBP and optimal treatment. This emphasizes the primary role of swallowing rehabilitation is that of affecting change in the physiologic components of swallowing, which influences bolus flow kinematics through the aerodigestive tract (Robbins, et al., 2008).
After initiating the clinical decision, we have a responsibility to provide ongoing evaluation of the plan by collecting internal evidence to ensure the intervention is appropriate and make needed adjustments. This can be completed through reevaluation of our standardized, validated assessments, updated instrumental swallow studies, and by creating our own data collection system within our clinic. The integration of EBP is a dynamic and ever-evolving journey!
References:American Speech-Language-Hearing Association. (2020). The Evidence-Based Practice Process. https://www.asha.org/research/ebp/evidence- based-practice-process/McCullough, G.H. (2002). One Application of Evidence-Based Medicine to Clinical Examinations of Swallowing. Perspectives on Swallowing and Swallowing Disorders. Dysphagia. https://doi.org/10.1044/sasd11.2.9Logemann, J.A. (2011). Debates in Dysphagia Management: How Do You Use Evidence-Based Practice in Your Dysphagia Patient Care? Perspectives on Swallowing and Swallowing Disorders. Dysphagia. https://doi.org/10.1044/sasd20.4.121Drisko, J. W., & Grady, M. D. (2019). Step 3 of EBP: Part 1—Evaluating Research Designs. Evidence-Based Practice in Clinical Social Work. Essential Clinical Social Work Series. https://doi.org/10.1007/978-3-030-15224-6_6Robbins, J., Butler, S.G., Daniels, S.K., Gross, R.D., Langmore, S., Lazarus, C.L, Martin-Harris, B., McCabe, D., Musson, N., Rosenbek, J. (2008). Swallowing and Dysphagia Rehabilitation: Translating Principles of Neural Plasticity Into Clinically Oriented Evidence. Journal of Speech, Language, and Hearing Research. https://doi.org/10.1044/1092-4388(2008/021)
