You cannot control but facilitate a fair, transparent, and scientific performance management system. To avoid biased reviews, appoint a reviewer to oversee the entire process who is either a superior boss or HR personnel. This individual will ensure a mutually agreed-upon review process and intervene in times of disagreement.
Additionally, consider implementing a 180 or 360-degree appraisal method. In a one-way appraisal method, the LM/RM can determine scores.
I am certain that senior professionals will provide further insights to enhance your understanding, as this is a vast area of expertise.
If you have any questions or need further clarification, please feel free to reach out.
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