title: Validation of a new method for the endoscopic measurement of post-bariatric gastric outlet using a standard guidewire: an observer agreement study.
abstract: OBJECTIVE
  Between 10 and 20% of all patients undergoing bariatric surgery procedures regain weight secondary to a gastrojejunostomy enlargement. The aim of this study was to validate the interobserver agreement while measuring gastric outlet diameters using a new standard guidewire.
  
  
  METHODS
  We selected thirty-five videos of consecutive endoscopic procedures on patients undergoing esophagogastroduodenoscopy after a Roux-en-Y gastric bypass procedure. All videos were evaluated by four raters: two expert endoscopists and two trainees. We excluded videos having a slipped Fobi ring or a strictured gastric outlet. Anastomosis diameter was measured using a novel device with standardized markings on a guidewire (Hydra jagwire, Boston Scientific, Natick. MA) as well as the current gold standard defined as a calibrated endoscopic measuring instrument (Olympus America, Center Valley, PA).
  
  
  RESULTS
  We obtained 272 measurements of the gastric outlet. Overall agreement measured through intra-class correlation coefficients for the gold standard was 0.84 (p < 0.01) and 0.83 (p < 0.01) for the new guidewire. Agreement among experts was 0.699 (p < 0.01), while among trainees it was 0.822 (p < 0.01).
  
  
  CONCLUSIONS
  The new guidewire demonstrated a high degree of observer reliability, also presenting similar results between expert endoscopists and trainees.
authors.affiliation: Department of Endoscopy and Bariatric Surgery, Kaiser Clinic and Day Hospital, São José do Rio Preto, SP, 15015-110, Brazil. gustavo_quadros@hotmail.com.|Department of Digestive Surgery, School of Medicine of ABC, Santo Andre, SP, 09080-650, Brazil. gustavo_quadros@hotmail.com.|Brazilian Bariatric Endoscopy International Group, São Paulo, Brazil. gustavo_quadros@hotmail.com.
authors.forename: Luiz Gustavo
authors.initials: LG
authors.lastname: de Quadros
authors.affiliation: Brazilian Bariatric Endoscopy International Group, São Paulo, Brazil.|Gastro Obeso Center, São Paulo, SP, 01308-000, Brazil.
authors.forename: Manoel Dos Passos
authors.initials: MD
authors.lastname: Galvão Neto
authors.affiliation: Brazilian Bariatric Endoscopy International Group, São Paulo, Brazil.|Department of Surgery, Federal University of Pernambuco (UFPE), Recife, PE, 50670-901, Brazil.
authors.forename: Josemberg Marins
authors.initials: JM
authors.lastname: Campos
authors.affiliation: Department of Endoscopy and Bariatric Surgery, Kaiser Clinic and Day Hospital, São José do Rio Preto, SP, 15015-110, Brazil.
authors.forename: Roberto Luiz
authors.initials: RL
authors.lastname: Kaiser Junior
authors.affiliation: Department of Digestive Surgery, School of Medicine of ABC, Santo Andre, SP, 09080-650, Brazil.|Brazilian Bariatric Endoscopy International Group, São Paulo, Brazil.
authors.forename: Eduardo
authors.initials: E
authors.lastname: Grecco
authors.affiliation: Department of Endoscopy and Bariatric Surgery, Kaiser Clinic and Day Hospital, São José do Rio Preto, SP, 15015-110, Brazil.
authors.forename: Mario
authors.initials: M
authors.lastname: Flamini Junior
authors.affiliation: Brazilian Bariatric Endoscopy International Group, São Paulo, Brazil.|Department of Surgery, Federal University of Pernambuco (UFPE), Recife, PE, 50670-901, Brazil.
authors.forename: Marcelo Falcao
authors.initials: MF
authors.lastname: de Santana
authors.affiliation: State University of Sao Paulo-Unesp-Ibilce, Rua Cristovão Colombo 2265, Sao Jose do Rio Preto, SP, 15054-000, Brazil.
authors.forename: Idiberto Jose
authors.initials: IJ
authors.lastname: Zotarelli Filho
authors.affiliation: Department of Surgery, Federal University of Pernambuco (UFPE), Recife, PE, 50670-901, Brazil.
authors.forename: Adriano Augusto Tomas Vasconcelos
authors.initials: AA
authors.lastname: Almeida Alexandre
mesh_terms: D000328:Adult; D000713:Anastomosis, Roux-en-Y; D050110:Bariatric Surgery / Q000379:methods*; D002138:Calibration; D019723:Endoscopes; D004724:Endoscopy / Q000379:methods*; D004867:Equipment Design; D005260:Female; D015390:Gastric Bypass / Q000379:methods; D006801:Humans; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D011446:Prospective Studies; D015203:Reproducibility of Results; D013270:Stomach / Q000601:surgery*
keywords: Gastric outlet; Measurement reliability; Observer agreement; Upper endoscopy; Weight recidivism; Weight regain