title: Development of a clinically relevant endoscopic grading system for chronic rhinosinusitis using canonical correlation analysis.
abstract: Diagnostic nasal endoscopy is a routine measure of sinonasal inflammation in patients with chronic rhinosinusitis (CRS). Although multiple staging systems have been proposed and evaluated, evidence of association between concurrent symptoms and endoscopic findings remains discordant. The goal of this study is to identify the relevant endoscopic attributes associated with symptom burden, and to systematically derive a weighted endoscopic scale that optimizes prediction of concurrent symptoms.
  
  
  
  Reported baseline symptom (22-item Sino-Nasal Outcome Test [SNOT-22]) and endoscopic evaluation scores (Lund-Kennedy [LK]) were obtained from patients with CRS enrolled in a prospective cohort study. Canonical correlation analysis of the SNOT-22 subdomains and LK variables was completed.
  
  
  
  A total of 629 patients were included in analysis including 343 with prior endoscopic sinus surgery. Significant canonical correlations outperformed aggregate correlations in explaining variance of the data (33% vs 3%, respectively). The first canonical correlation was dominated by the rhinologic symptom domain and the endoscopic polyp score (r = 0.54; p < 0.05) whereas additional significant canonical correlation was found between the extra-rhinologic symptom subdomain and the edema score in patients without prior ESS (r = 0.21; p < 0.05), and discharge in patients with prior ESS (r = 0.22; p < 0.05). All other domains and endoscopic variables did not significantly contribute to the canonical correlation.
  
  
  
  Although aggregate symptoms and endoscopic scores demonstrate minimal correlation, a weighted combination of symptom domains and endoscopic attributes greatly improves this correlation. A simple approximation of the weights of each of the endoscopic variables of polyps, edema, discharge, scarring, and crusting, is an approximate ratio of 4:2:1:0:0, respectively.
authors.affiliation: Department of Surgery, Division of Otolaryngology-Head and Neck Surgery, University of California, San Diego, San Diego, CA.
authors.forename: Adam S
authors.initials: AS
authors.lastname: DeConde
authors.affiliation: Department of Psychology, Portland State University, Portland, OR.
authors.forename: Todd E
authors.initials: TE
authors.lastname: Bodner
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Oregon Health and Science University, Portland, OR.
authors.forename: Jess C
authors.initials: JC
authors.lastname: Mace
authors.affiliation: Division of Otolaryngology, University of Utah School of Medicine, Salt Lake City, UT.
authors.forename: Jeremiah A
authors.initials: JA
authors.lastname: Alt
authors.affiliation: Division of Otolaryngology-Head and Neck Surgery, Department of Surgery, University of Calgary, Calgary, Alberta, Canada.
authors.forename: Luke
authors.initials: L
authors.lastname: Rudmik
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Oregon Health and Science University, Portland, OR.
authors.forename: Timothy L
authors.initials: TL
authors.lastname: Smith
mesh_terms: D000328:Adult; D000368:Aged; D002908:Chronic Disease; D004724:Endoscopy; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009298:Nasal Polyps / Q000175:diagnosis / Q000601:surgery; D012220:Rhinitis / Q000175:diagnosis* / Q000601:surgery; D012720:Severity of Illness Index; D012852:Sinusitis / Q000175:diagnosis* / Q000601:surgery
keywords: chronic disease; endoscopy; epidemiologic measurements; sinusitis; statistics