title: Esophageal manometry: assessment of interpreter consistency.
abstract: OBJECTIVE
  Manometry is used widely in the evaluation of esophageal disorders. Our aim was to assess the intra- and interobserver reliability of esophageal manometry and identify potential causes for diagnostic variability.
  
  
  METHODS
  Seventy-two esophageal manometry tracings were selected randomly from archives. Eight interpreters randomly and blindly evaluated tracings. Interpreters were divided into 3 groups: highly experienced (N = 3), moderately experienced (N = 3), and inexperienced (N = 2). Each tracing was examined for abnormalities involving the lower-esophageal sphincter (LES) and esophageal body. Interpreters rendered a single diagnosis from a list of 7 manometric diagnoses: normal, nutcracker, hypertensive LES, hypotensive LES, diffuse esophageal spasm (DES), nonspecific/ineffective esophageal motility (IEM), and achalasia. Intra- and interobserver agreements were determined and reasons for varied diagnoses were investigated.
  
  
  RESULTS
  Overall intraobserver agreement was good (kappa = .63, P < .0001). There was no difference ( P = .9) between the highly and midexperienced interpreters (kappa = .61 and .65, respectively). Interobserver agreement for the diagnosis of achalasia and normal motility was good (kappa = .65 and .56, respectively). However, other manometric diagnoses yielded only fair interobserver agreement (kappa = .27). DES, nonspecific/ineffective esophageal motility (IEM), and hypo- and hypertensive LES diagnoses showed the least agreement. Poor adherence to established manometric criteria, misinterpretation of intrabolus pressure, and technical inadequacy were the most common sources of inconsistency in interpretations.
  
  
  CONCLUSIONS
  Manometric diagnoses of conditions other than normal or achalasia are variable and have poor interobserver variability. Given their uncertain clinical implications, we must either redefine them or eliminate them from practice.
authors.affiliation: Department of Gastroenterology and Hepatology, Center for Swallowing and Esophageal Disorders, Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, Ohio 44195, USA.
authors.forename: Devjit S
authors.initials: DS
authors.lastname: Nayar
authors.forename: Farah
authors.initials: F
authors.lastname: Khandwala
authors.forename: Edgar
authors.initials: E
authors.lastname: Achkar
authors.forename: Steven S
authors.initials: SS
authors.lastname: Shay
authors.forename: Joel E
authors.initials: JE
authors.lastname: Richter
authors.forename: Gary W
authors.initials: GW
authors.lastname: Falk
authors.forename: Edy E
authors.initials: EE
authors.lastname: Soffer
authors.forename: Michael F
authors.initials: MF
authors.lastname: Vaezi
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004935:Esophageal Diseases / Q000175:diagnosis* / Q000453:epidemiology*; D005260:Female; D006801:Humans; D008297:Male; D008365:Manometry / Q000706:statistics & numerical data*; D008875:Middle Aged; D015588:Observer Variation; D011446:Prospective Studies; D015203:Reproducibility of Results; D016037:Single-Blind Method