Medical Credentialing for Physicians and Healthcare Practitioners. You need someone to look out for you in the bureaucratic nightmare that is the existing medical credentialing system. Every state, every hospital, every insurance company has different rules, forms, processes and requirements for medical billing and credentialing. And just when you think you may be getting a grasp, it changes! Michelle McFarlane, RN, MSN, MBA and the highly professional staff at AddVal Inc. have the unparalleled medical credentialing experience to deliver meaningful benefits to your practice.