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Filters add search terms to narrow your results.

  • Filter options appear to the left of your results.
  • Click on a filter to apply it to your search. Active filters appear above your search results.
  • Filters "stick" and are applied to future searches until you turn them off.
  • Only the most popular filters display by default. Click Show additional filters to view more options.
  • Selecting multiple filters from one category will add the filters with "OR," expanding your results.

Note: Only filters which are valid for your search results will appear. For example, if no Clinical Trials are in your results, the filter for Clinical Trials will not appear.

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Last Reviewed: October 28, 2019