Sources of employee performance ratings
The backbone of any appraisal process, is the collection and evaluation of performance data about the employee in question. Your goal for any measure you use, is to ensure they are reliable, valid and relevant. Reliability means they're consistent predictors. Valid means they measure what they say they measure. And relevant means that what was measured was clearly related to performance in the job. Now, before we get started don't forget that it's very important to have a well trained expert help you select and approve the measures, you'll use for the employee appraisal process.
This not only ensures a more productive system, but it also helps cover you later if you ever, unfortunately, find yourself needing to defend your choices in court. Okay, there are three main types of things that you might want to measure. Traits, behaviors and outcomes. Let's start with traits. Here, we're generally referring to aspects of one's personality or attitudes. The questions here is whether or not we can measure personality traits.Source: https://www.linkedin.com/learning/performance-review-foundations/sources-of-employee-performance-ratings