WebMD Editors determine the topics and placement on our lists through a process involving the evaluation of user activity on WebMD and population statistics available through government agencies and professional organizations. The topics are not ranked by most popular to least popular. All topics on a list are of relatively equal weight and are simply numbered for ease. If a sponsor or advertiser on WebMD happens to be affiliated with a topic on one of our lists, it is purely coincidental. Nothing should be implied by the topics or order of the list except for the fact that all the topics generate the most interest on WebMD and in our population at large.

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