Systemic review on highly qualified screening tests for swallowing disorders following stroke: Validity and reliability issues

Background: Oropharyngeal dysphagia following stroke enhances the risk of dehydration, malnutrition, aspiration pneumonia, persistent disablement, and even death. Screening of dysphagia has been shown to positively change health outcomes. The aim of the present study was to systematically introduce the published swallowing screening methods in patients with stroke and their appropriateness for detecting swallowing disorders following stroke with an emphasis on the methodological quality of their research studies. Materials and Methods: A computerized search through the Medline (PubMed), Embase, Scopus, and Google Scholar; databases from 1990 through 20 July 2013 was performed. In addition, the related citations and reference lists of the selected articles were considered. Results: A total of 264 papers were retrieved and 19 articles finally met inclusion criteria. Sixty-eight percent of included papers did not have a sufficient quality and only six articles were scored as having evidence level ‘I’ and were reported descriptively. The most prevalent bias in the included studies was probably a kind of spectrum bias that could lead to select just a subgroup of admitted stroke patients. The screening tests’ sensitivities ranged from 47 to 100%, while their specificities ranged from about 63 to 100%. Strengths and limitations of each test have been discussed. Conclusion: We ultimately found four simple, valid, reliable, sensitive, and specific tests for screening swallowing disorders in the almost all acute alert stroke patients. Further validation and reliability assessing of screening tests need to follow a very accurate and well-established method in a large sample of the almost all acute alert stroke patients admitted to the hospitals.