{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,7]],"date-time":"2026-05-07T21:40:34Z","timestamp":1778190034272,"version":"3.51.4"},"reference-count":36,"publisher":"PeerJ","license":[{"start":{"date-parts":[[2023,2,21]],"date-time":"2023-02-21T00:00:00Z","timestamp":1676937600000},"content-version":"unspecified","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"abstract":"<jats:sec>\n               <jats:title>Background<\/jats:title>\n               <jats:p>The number of patients with proton pump inhibitor (PPI)-refractory reflux symptoms is underestimated since many patients resign after an unsuccessful therapy attempt. Thus, it would be useful having a non-invasive tool that can help identify true gastroesophageal reflux disease (GERD) patients in order to manage them early and properly. The GerdQ is a validated tool developed for this purpose but its applicability in PPI-refractory patients has not yet been investigated. Our aim was to investigate if reflux symptoms per se, the GerdQ and patients characteristics are suitable for non-invasive diagnosis of GERD in patients with PPI refractory reflux symptoms.<\/jats:p>\n            <\/jats:sec>\n            <jats:sec>\n               <jats:title>Methods<\/jats:title>\n               <jats:p>A total of 500 patients from a prospectively recorded data base with PPI-refractory reflux symptoms were retrospectively analyzed. All patients received comprehensive diagnostic workup including EGD, pH-impedance measurement and manometry. GERD was diagnosed according to the recent Lyon consensus.<\/jats:p>\n            <\/jats:sec>\n            <jats:sec>\n               <jats:title>Results<\/jats:title>\n               <jats:p>Of all patients enrolled in the study, 280 (56%) finally fulfilled the criteria for objectively verified GERD according to the Lyon consensus. There were no significant differences in age and gender between the patients with and without GERD, whereas the body mass index was significantly higher in the group with verified GERD, but the discriminative value was low (Welch-Test, <jats:italic>p<\/jats:italic>\u00a0&lt;\u00a0.001, Cohen\u2019s d = 0.39). Furthermore, there were no significant differences in the GerdQ values between the two groups. A GerdQ cutoff value \u2265 9 resulted in a sensitivity of 43% and specificity of 57% with a positive predictive value of 56% and a negative predictive value of 44%.<\/jats:p>\n            <\/jats:sec>\n            <jats:sec>\n               <jats:title>Conclusion<\/jats:title>\n               <jats:p>Based on our study, neither symptoms and the GerdQ score nor patients\u2019 characteristics are appropriate tools to distinguish between GERD and other causes for reflux symptoms in patients with PPI-refractory reflux symptoms.<\/jats:p>\n            <\/jats:sec>","DOI":"10.7717\/peerj.14802","type":"journal-article","created":{"date-parts":[[2023,2,21]],"date-time":"2023-02-21T09:59:19Z","timestamp":1676973559000},"page":"e14802","source":"Crossref","is-referenced-by-count":3,"title":["Symptoms, the GerdQ score and patients\u2019 characteristics do not predict gastroesophageal reflux disease in patients with proton-pump-inhibitor-refractory reflux symptoms\u2014results from a large prospective database"],"prefix":"10.7717","volume":"11","author":[{"given":"Joachim","family":"Labenz","sequence":"first","affiliation":[{"name":"Department of Medicine, Diakonie Hospital Jung Stilling, Siegen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Merlissa","family":"Menzel","sequence":"additional","affiliation":[{"name":"Phillips-Universit\u00e4t Marburg, Marburg, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Oliver","family":"Hirsch","sequence":"additional","affiliation":[{"name":"FOM University of Applied Sciences, Siegen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Matthias","family":"M\u00fcller","sequence":"additional","affiliation":[{"name":"Department of Medicine, Diakonie Hospital Jung Stilling, Siegen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Christian","family":"Labenz","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine I, 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