Frequency of Probable RBD Among NACC Participants Note: An Official Proposal has not been Submitted to NACC. Lead Investigator: Bradley Boeve Institution : Mayo Clinic E-Mail : bboeve@mayo.edu Proposal ID : 1696 Proposal Description: Aim: To determine the frequency of probable RBD across racial/ethnic groups and diagnoses in the NACC We seek to determine the frequency of probable RBD (based on a positive responses on RBD questions - particularly A5 q5j, B9 q9h, D2 q15) across racial/ethnic groups (A1 fields) and diagnoses (D1 fields). These data will likely assist in determining recruitment strategies for identifying minority participants with RBD for a new NIH-funded program (NAPS2) focused on RBD. If possible, a subset of this dataset among those who have had the LBD Module completed would also be valuable if those who have any ???yes?? responses on q1 of form E3L could be designated - even if done as a separate file.