1 (If you don't know what these, are set them each to 0.5. 2  z is the value that specifies the level of confidence you want in your confidence interval when you analyze your data. 3  Typical levels of confidence for surveys are 95%, in which case z is set to 1.96. 4  E sets the accuracy of your sample proportions.
A hepatobiliary (HIDA) scan is an imaging procedure used to diagnose problems of the liver, gallbladder and bile ducts. For a HIDA scan, also known as cholescintigraphy and hepatobiliary scintigraphy, a radioactive tracer is injected into a vein in your arm.
Gallstones are hard deposits that form inside the gallbladder. Gallstones may be as small as a grain of sand or as large as a golf ball. The cause of gallstones varies. There are two main types of gallstones: 1  Stones made of cholesterol. This is the most common type. Cholesterol gallstones are not related to cholesterol levels in the blood.  Stones made of bilirubin. These are called pigment stones. They occur when red blood cells are destroyed and too much bilirubin is in the bile.