However, the most accurate study to diagnose GERD is a 24-hour pH monitoring in lower esophagus; where a thin tube with an electrode attached is placed inside the esophagus in order to detect how long the acid reflux stays in there.

然而，诊断GERD的最精确的方法是在24小时食管下段pH监测，在食道内放置一个带有电极的细管，以监测酸反流在食道内停留的时间。