Conducting Complaint Investigations in Non-Accredited, Non-

5510 - Conducting Complaint Investigations in Non-Accredited, Non- Exempt Laboratories (Rev. 234; Issued: 09-12-25; Effective: 09-12-25; Implementation: 09-12-25) The SA may contact CMS for guidance on the type of complaint investigation which may include one or more of the following: on-site survey, telephone, electronic communication, letter, or a documentation review depending on the complaint. Complaint investigations are unannounced. NOTE: The SA should contact CMS when an unannounced complaint survey is problematic, such as when a laboratory will not permit an investigation. For on-site complaint investigations, the SA performs a full or partial survey based on the allegations. If a complaint alleges generalized inappropriate laboratory practices, the SA evaluates compliance with applicable requirements or conducts a full survey, as needed. If the complaint is of a specific nature, the SA performs a survey focused on areas relevant to the complaint. However, if the SA discovers systemic issues on the focused survey, the survey may be expanded to a full survey.