Effective performance is really a situation-specific variable that can only be defined by organizational standards and expectations. Instruments used for appraisal must be both valid and reliable and must be free from race and sex discrimination practices. Test reliability is defined as the consistency with which an instrument measures what it is supposed to measure. Test reliability is an extremely important concern for test developers.

Constructs must perform their measurement function consistently and must measure what they are designed to measure, over time. Reliability does not guarantee validity, but is a necessary condition for test validity. The instruments selected to assess performance should reflect the specific purpose of appraisal. Rating scales are used to assess behaviors on the job compared with general normed behaviors, literature-based behaviors, or local criteria. Essential interpersonal skills is an example of a behavior suitable for a rating scale.

Objective instruments are based on valid and reliable criteria. With objective measures, such as checklists and goal setting, certain local standards are determined and used as assessment variables. Checklists can also be used to assess progress or progressive steps in meeting criteria. Goal setting relates to the goal-setting theory models and can assess behavior and stimulate motivation.