Changes in the CO DWC Rule 16 – Utilization Standards. The new rules, effective 01/01/16, require peer reviewers to be either Level I or Level II Accredited with DWC in order to review prior authorization requests for medical reasons. The difference between the two levels is that Level II Accreditation allows providers to perform impairment ratings. Information regarding DWC’s Accreditation process for Level I Accreditation is available here: https://www.colorado.gov/