title: Open access capture of patients with gastroesophageal reflux disease using an online patient-reported outcomes instrument.
abstract: BACKGROUND
  Persons with gastroesophageal reflux disease (GERD) frequently search online for information about causes and treatment options. The GerdQ self-assessment questionnaire can be used for diagnosis of GERD and follow-up of symptoms.
  
  
  OBJECTIVE
  To assess whether it is feasible (1) to study the prevalence and impact of GERD in persons visiting a GERD information website, and (2) to identify partial responsiveness to proton pump inhibitor (PPI) therapy using the GerdQ.
  
  
  METHODS
  All visitors (aged 18-79 years) to a GERD information website between November 2008 and May 2011 were invited to complete the GerdQ online. The GerdQ questionnaire consists of 6 questions (score per question: 0-3). In respondents who did not use PPIs, we used the questionnaire to identify those with GERD (total score ≥8) and assess the influence of these symptoms on their daily life, divided into low (total score <3 on impact questions) and high impact (total score ≥3 on impact questions). In PPI users, we used the GerdQ to quantify partial responsiveness by any report of heartburn, regurgitation, sleep disturbance, or over-the-counter medication use for more than 1 day in the preceding week. We subsequently asked GerdQ respondents scoring ≥8 to complete the disease-specific Quality of Life in Reflux and Dyspepsia (QOLRAD) questionnaire.
  
  
  RESULTS
  A total of 131,286 visitors completed the GerdQ, of whom 80.23% (n = 105,329) did not use a PPI. Of these, we identified 67,379 respondents (63.97%) to have GERD (n = 32,935; 48.88% high impact). We invited 14,028 non-PPI users to complete the QOLRAD questionnaire, of whom 1231 (8.78%) completed the questionnaire. Mean total QOLRAD scores were 5.14 (SEM 0.04) for those with high-impact GERD and 5.77 (SEM 0.04) for those with low-impact GERD (P < .001). In PPI users, 22,826 of 25,957 respondents (87.94%) reported partial responsiveness. We invited 6238 PPI users to complete the QOLRAD questionnaire, of whom 599 (9.60%) completed the disease-specific quality-of-life questionnaire. Mean total QOLRAD scores were 4.62 (SEM 0.05) for partial responders and 5.88 (SEM 0.14) for adequate responders (P < .001).
  
  
  CONCLUSIONS
  The GerdQ identified GERD in many website respondents and measured partial responsiveness in the majority of PPI users. Both non-PPI users with GERD and PPI users with partial responsiveness were associated with a decreased health-related quality of life. We have shown the feasibility of GERD patient identification online.
authors.affiliation: Department of Gastroenterology and Hepatology, Radboud University Medical Center, Nijmegen, Netherlands. M.Tielemans@MDL.umcn.nl.
authors.forename: Merel M
authors.initials: MM
authors.lastname: Tielemans
authors.forename: Jan Bmj
authors.initials: JB
authors.lastname: Jansen
authors.forename: Martijn Gh
authors.initials: MG
authors.lastname: van Oijen
keywords: Gastroesophageal reflux; Internet; open access questionnaire; partial responsiveness; proton pump inhibitor