1990, Masclee AA, de Best AC, de Graaf R, Cluysenaer OJ, Jansen JB, “Ambulatory 24-hour pH-metry in the diagnosis of gastroesophageal reflux disease: determination of criteria and relation to endoscopy”, in Scand J Gastroenterol, volume 25, number 3, →PMID, pages 225–230:
Long-term ambulatory pH-metry is of clinical value in detecting pathologic reflux in symptomatic patients with negative endoscopy.
2011, Datta K, Datta R, Venkatesh MD, Dey D, Jaipurkar R, “24-hour dual-probe ambulatory pH-metry findings in cases of laryngopharyngeal reflux disease”, in J Laryngol Voice[1], volume 1, number 1, pages 18–21:
Laryngopharyngeal reflux disease (LPRD) cases are common in clinical practice and usually neglected for want of a definitive diagnosis. Diagnosis requires a documented evidence of fall in pH levels in the laryngopharynx with dual-probe 24-hour ambulatory pH-metry. […] Dual-sensor pH-metry is confirmatory for establishing diagnosis of LPRD.
