Cut scores are test scores used in mastery testing and in certification tests to identify those test takers who
appear to have achieved at a predetermined level of proficiency. Cut scores are often used to differentiate test
takers on a pass-fail basis. This paper takes up points raised by Berk (2000), discussing the use of reliability
and error indices which are particularly appropriate for testing procedures which use cut scores. It is
suggested that these indices are still not widely used. In an effort to promote their use and interpretation,
results derived from instruments developed by testing centers in a variety of countries are presented.