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Evidence Based Dentistry: Step 3: Acquire

Filtered Resources

Filtered Resources

These results you find in these databases have already been analyzed and you are receiving the best results, but you may be missing some more recent research that has not yet been reviewed and filtered.  If you are looking for filtered results, you can search the following:


Acquire Information

Levels of Evidence

The level of evidence you need will determine where you will search.  It is always a good idea to use the highest available level of evidence in your results.  The resources you use can be divided into two categories:  filtered and unfiltered.  High quality filtered studies are preferred, but are not always the most appropriate. 

Study Types

What Type Of Study Should I Look For?

Type of Question

Suggested Study


Systematic Review, Meta-Analysis

Diagnostic Testing

Prospective, blind comparison to Gold Standard


Cohort Study > Case Control > Case Series


RCT > Cohort Study > Case Control > Case Series


RCT > Cohort Study > Case Control > Case Series


RCT > Cohort Study > Case Control > Case Series


Economic Analysis

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Conducting Your Search

Conducting Your Search

Once you have selected the databases you wish to search, you will combine the keywords you identified when creating your PICOT question and search for them in the databases.  For more information about the searching process, see: 

Unfiltered Resources

Unfiltered Resources

If you cannot find filtered results for your search or you want to check more recent research, you might want to check through unfiltered resources.  These resources contain primary research that has not been analyzed.  Many are also specific to certain topics.  Select your databases carefully  The ECU list of databases provides information to help you select the appropriate database for your search.  The following resources contain unfiltered results: