In a performance appraisal, the term validity refers to whether the appraisal measures all aspects of performance, both relevant and irrelevant.

Performance Appraisal

A systematic evaluation process of an employee's job performance and productivity in relation to certain pre-established criteria and organizational objectives.

Validity

The extent to which performance on a measure (such as a test score) is related to what the measure is designed to assess (such as job performance).

Relevant

Pertaining to or connected with the matter at hand; applicable or significant to the topic being discussed.