A free online symptom-checker for patients

"Mr. Maude, a former equity analyst who lives in the U.K., developed a program which providers pay to use, and named it for his daughter, now 17, who had chickenpox at the age of 3. She developed a life-threatening infection, necrotizing fasciitis, that is a common complication but was missed at the time. In a study co-authored by Dr. Graber in the Journal of General Internal Medicine in 2007, Isabel suggested the correct diagnosis in 48 of 50 complex cases, or 96%. (Dr. Graber has no financial or other ties to Isabel.)
Last November, Isabel launched a free online symptom-checker for consumers that can take a pattern of symptoms that patients enter in everyday language and instantly compute the most likely diagnoses from its database of 6,000 diseases, while pushing the more far-out possibilities down the list."

http://symptomchecker.isabelhealthcare.com/home/default

Source: WSJ, 23 July 2013: "A Better Online Diagnosis Before the Doctor Visit".