Behaviorally anchored rating scales

In psychology research on behaviorism, Behaviorally Anchored Rating Scales (BARS) are scales used to report performance. BARS are normally presented vertically with scale points ranging from five to nine.

BARS Behaviorally Anchored Rating scales is a method that combines elements of the traditional rating scales and critical incidents methods. In order to construct BARS seven steps are followed as mentioned below
# Examples of effective and ineffective behavior related to job are collected from people with knowledge of job.
# These behaviors are converted in to performance dimensions.
# A group of participants will be asked to reclassify the incidents. At this stage the incidents for which there is not 75% agreement are discarded as being too subjective.
# Then the above mentioned incidents are rated from one to nine on a scale.
# Finally about six to serve incidents for each performance dimensions- all meeting retranslation and standard deviation criteria will be used as BARS.

This is by far the best method used for a performance appraisal method

This is the official Performance Appraisal method of Midas.