Instruments evaluating the clinical findings of laryngopharyngeal reflux: A systematic review

To identify the instruments for evaluating the clinical findings (ICFs) of laryngopharyngeal reflux (LPR) designed for use with regard to diagnosis and treatment effectiveness.

The PubMed, Scopus, and Cochrane databases were used to search for subject headings following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) recommendations. Three investigators retrieved relevant studies published between 1990 and 2018 describing the evolution of laryngopharyngeal findings throughout LPR treatment. Issues of clinical relevance, that is, LPR diagnosis, treatments, and signs assessed for diagnosis or as therapeutic outcomes, were assessed. The investigators also evaluated the psychometric properties (conceptual model, content validity, consistency, reliability, concordance, convergent validity, known-groups validity, responsiveness to change, and interpretability) of the ICF. The risk of bias was assessed with the tool of the Clarity Group and Evidence Partners.

The search identified 1,227 publications with a total of 4,735 LPR patients; of these studies, 53 met the inclusion criteria. Of these 53 studies, we identified 10 unvalidated and six validated ICFs. None of the validated ICFs included all the psychometric properties. The main identified deficiencies related to ICF psychometric validation included variable construct validity, disparate and uncertain reliabilities, and a lack of interpretability. The lack of consideration of certain LPR laryngeal and extralaryngeal signs is the main weakness of ICFs, biasing content, and construct validities.

The low specificity of LPR signs, the lack of consideration of many findings, and the absence of a gold standard for diagnosis constitute barriers to the further validation of these ICFs. Additional studies are needed to develop complete and reliable ICFs. Laryngoscope, 129:720-736, 2019.