Generally CDM and biostats work under one big department, DM and Biostats:

Clinical Data Manager: health science background, knowledge of CDMS, eg OC, Clintrial, or oracle-based, strong reading and writing skills in edit checks, knowledge of clinical-related issues, like medical terminology, healthcare system etc

Biostatistician: MSc of Stats or Biostats, knowledge of SAS, R, can read and write scientific paper