Yielding the same or compatible results in different clinical experiments or statistical trials.
Reliability is the consistency of measurement, or the degree to which an instrument measures the same each time it is used under the same condition with the same subjects. In short, it is the repeatability of the measurement. A measure is considered reliable if a person's score on the same test given twice is similar. It is important to remember that reliability is not measured, it is estimated. (Social Research Methods)