Why is the ninth month called September?
Bernstein test Bern·stein test (bûrn'stīn', -stēn')
A test to establish that substernal pain is due to reflux esophagitis, performed by instillation of a weak solution of hydrochloric acid directly into the lower esophagus. The symptoms disappear when the acid solution is replaced by normal saline solution. Also called acid perfusion test.