eMedicine, acquired by WebMD in January 2006, is home to the largest and most current Clinical Knowledge Base available to physicians and other healthcare professionals. The eMedicine Clinical Knowledge Base contains 30,000 multimedia files and features the largest online repository of medical education credits for physicians, nurses, and optometrists. eMedicine’s subscription site for institutions is www.iMedicine.com. Nearly 10,000 physician authors and editors contribute to the eMedicine Clinical Knowledge Base, which contains articles on 7,000 diseases and disorders. The evidence-based content, updated 24/7 provides the latest practice guidelines in 59 medical specialties. eMedicine's professional content undergoes 4 levels of physician peer review plus an additional review by a PharmD prior to publication.