CREDENTIALING XPERTS! CREDX is a professional credentialing service that saves your business both time and personnel investment to complete the lengthy credentialing process. Count on CREDX to keep your focus on patients, not paperwork. CredX clients include: Physicians, MDs, Doctors, Psychiatrists, Psychologists, Therapists, Counselors, Chiropractors, Physical Therapists, Occupational Therapists, Speech Pathologists, Groups, DME, among others.