Esophageal pH monitoring developed a dependable external reference electrode. Using this technique to monitor esophageal acid exposure patients for periods up to 24 hours, DeMeester and Johnson were able to identify the most important parameters of esophageal acid exposure, and they developed a composite pH score to quantify gastroesophageal reflux. The initial 24-hour pH studies required hospitalization until the introduction of microcircuits in the 1980s that allowed portable esophageal pH monitoring in an outpatient setting. Gastroesophageal reflux disease (GERD) is a common disease in western countries. In the United States, 7% of the population experiences heartburn daily and 44% at least once a
Fecal pH test milliliter of feces is collected and a strip of nitrazine paper is dipped in the sample and compared against a color scale. A pH of less than 5.5 indicates an acidic sample. Unhealthy individuals with a higher or lower pH rate have been observed having a higher mortality rate. A high alkaline pH rating being associated with the body's inability to create enough acid along with undigested food. Fecal pH test A fecal pH test is one where a specimen of feces is tested for acidity in order to diagnose a medical condition. Human feces is normally acidic. An acidic