From the Library's version of PubMed, you will see Duke-selected filter options available in the top left sidebar of the search results page (under the MY NCBI FILTERS header) that you can use to refine your search. For example, you can choose to only look at only systematic reviews or only therapy/randomized control trials (RCTs).
Don't check any of the Abstract, Free Full Text, or Full Text options as doing so will cause you to miss items Duke subscribes to on your behalf.
Show Additional Filters
The default list of filters in the left hand sidebar does not include all options. Scroll down and click the link "Choose additional filters" to add filters to the list. Filters are available to focus your search results by article types, publication dates, species, languages, sex, subjects, journal categories, ages, and search fields. Click on the boxes to activate the filters (or to make them show up next to your search results). You then much check them to apply them to your specific search.
Type of Article, Species, Sex, and Ages filters are based on terms added by NLM. When these filters are selected they remove very recent articles that have not yet been indexed (or had MeSH terms added). To make sure you aren't missing the most recent research, look at the most recent search results before adding these filters.
Additional Filters box:
Activated Filters Display on Search Result Pages. Filters stay selected and shown until you change or clear them.
Once the filters are selected on the above screenshot they appear as boxes on the left hand of the screen on the results page. Tick those boxes to filter your search results.
Research Study Filters
Add options to the "Article types" list by clicking on the "Additional Filters" link on the left of search result screen and selecting ones you want to use.
Therapy, intervention, and prevention search results can be limited to articles reporting clinical research by selecting Clinical Trial, Meta-Analysis, Randomized Control Trial or Systematic Reviews from the "Articles types" list.
You can then select the filter you want. Then check the left hand box to have it appear in the search results.
Other Research Article Type Filters
Quoted definitions are from the PubMed MeSH Browser (link below).
You can use field tags in PubMed to limit your search to only the specified fields of the citations. For instance, you can add a title field tag and only search for a word or words in article titles. Without field tags, PubMed defaults to searching every field of a citation. This means you're searching the article title, abstract/summary, author-supplied keywords, PubMed indexing terms, and other fields like author names, authors' institutions, journal names, etc.
If your search seems to have too many irrelevant results, using field tags can help narrow your search. To use field tags, add the code in brackets immediately following the search term. For instance, to only search for dogs in the titles of articles, you'd search for dogs[TI] in PubMed.
A list of common field tags is below:
|Citation||Topic tags||Other tags of interest|
Publication Date [DP]
Text Words [TW]
MeSH Terms [MH]
MeSH Major Topic [MAJR]
MeSH Subheadings [SH]
Supplementary Concept [NM]
Pharmacological Action [PA]
Publication Type [PT]
Entrez Date [EDAT]
First Author Name [1AU]
Grant Number [GR]