Which of the following procedures is mandated for assisted living centers to investigate?

The mandated procedure for assisted living centers to investigate is related to incidents of abuse and neglect. This requirement is put in place to ensure the safety and well-being of residents, who may be vulnerable due to age, health status, or other factors. Investigating abuse and neglect incidents is critical in identifying and addressing any harmful situations, thereby protecting residents from potential mistreatment. This procedure helps maintain a safe environment, allows for accountability, and ensures that any violations of residents' rights are appropriately addressed.

In contrast, while resident satisfaction, facility complaints, and staff performance evaluations are important aspects of the operation and quality of care in assisted living centers, they do not carry the same legal and ethical obligations to investigate as incidents of abuse and neglect. Regular reviews of those areas can improve service quality and promote a positive living environment, but they do not directly involve the urgent need to protect residents from harm.