Subject Guides: PICO: Form a Focused Clinical Question: 3b. Acquire: Searching

Getting Started

By now you should have determined the key terms from your PICO question and relevant synonyms. Read the tips below to see best determine how to search each database for those terms.

Boolean Operators

Get a refresher on how to use AND, OR, & NOT in your search strategy.

Subject vs. Keyword

Subject headings describe the content of each item in a database usually using a controlled vocabulary. Use these headings to find relevant items on the same topic. Searching by subject headings is the most precise way to search article databases.

It is not easy to guess which subject headings are used in a given database. Look for a link titled "headings" or "thesaurus" in each database to search for subject headings.

MeSH stands for Medical Subject Headings and are the subject headings used in PubMed.

Keyword searching is how you typically search web search engines. Think of important words or phrases and type them in to get results.

Here are some key points about each type of search:

Keywords	vs.	Subjects
natural language words describing your topic; good to start with		pre-defined "controlled vocabulary" words used to describe the content of each item (book, journal article) in a database
more flexible to search by; can combine together in many ways		less flexible to search by; need to know the exact controlled vocabulary term
database looks for keywords anywhere in the record; not necessarily connected together		database looks for subjects only in the subject heading or descriptor field, where the most relevant words appear
may yield too many or too few results		if too many results, also uses subheadings to focus on one aspect of the broader subject
may yield many irrelevant results		results usually very relevant to the topic

Source: Database Search Tips: Keywords vs. Subjects by MIT Libraries

These tutorials will show you how to search for your topic using the MeSH terms you identified previously.

PubMed Online Tutorial: MeSH in MEDLINE/PubMed

This 4-minute interactive tutorial demonstrates how automatic term mapping and MeSH term "explosion" can enhance your PubMed search.

NLM Tutorial: PubMed Subject Search: How It Works

Medical Subject Headings (MeSH®) in MEDLINE®/PubMed®: A Tutorial
This brief and interactive tutorial is designed to help you:

- Understand the purpose and structure of the Medical Subject Headings (MeSH) and
- Use MeSH to search MEDLINE®/PubMed® for medical literature and information.

Database Searching Tips and Tutorials

Basic Database Searching Tips

Use the MeSH terms and synonyms you've identified for your question's concepts, and combine them in a database search.

Start broad and then narrow down your search;
Use the database's filters to limit your results;
Be sure to sort by relevance/best match (especially important in PubMed);
Don't limit to Full Text right away -- you can access full text through the Medical Library licensed resources, or you can request articles we don't own through Interlibrary Loan.

For advanced users:

For more focused results, try searching PubMed's Clinical Queries. This search interface automatically applies optimized filters based on your question's clinical domain.

Video Tutorials and Interactive Training Courses

Using PubMed in Evidence-Based Practice Training Course

This 30-minute interactive tutorial helps clinicians develop a clinical question using the PICO framework and efficiently find relevant biomedical literature using PubMed. Click on the image below to open a new browser tab or window to start the tutorial, or click here.

Choose a Database

Database Selection

Choose a database from our Databases A-Z list, filtered to evidence-based resources, or start searching from one of the selected EBM resources below.

ACP Journal Club
ACP Journal Club is a monthly feature of Annals of Internal Medicine that summarizes the best new evidence for internal medicine from over 130 clinical journals.

Cochrane Library This link opens in a new window
Collection of EBM databases, including full text of Cochrane systematic reviews with references and search information. Mobile friendly.
DynaMedex This link opens in a new window
Combines the clinical expertise and curated disease content of DynaMed with the treatment options and drug information of Micromedex; provides evidence-based insights for optimal clinical decision-making and improved patient outcomes. Mobile friendly. App available.
Essential Evidence Plus This link opens in a new window
Evidence-based clinical decision support tool. Personal account required to access content. Features summaries, guidelines, literature reviews, and calculators. Patient Oriented Evidence that Matters (POEMs) research summaries may be emailed daily. Mobile friendly.
ECRI Guidelines Trust This link opens in a new window
ECRI Guidelines Trust is a publicly available web-based repository of objective, evidence-based clinical practice guidelines for patient care. This centralized repository includes current evidence-based guidance developed by nationally- and internationally-recognized medical organizations and medical specialty societies.
PEPID This link opens in a new window
Clinical Rotation Companion Platinum; includes adult and pediatric disease diagnostics and treatment information, lab values, an extensive drug database (including herbals), ICD codes, Stedman's Dictionary of Terms, anatomical illustrations, and more. App available.
Trip Database This link opens in a new window
A meta-search engine for sources of high quality internet information, including PubMed’s clinical queries and government guidelines. It has EBM-based features such as a PICO search, evidence filters, and rapid review. Mobile friendly.
UpToDate This link opens in a new window
Evidence-based, peer reviewed clinical information. Please note: Access is limited to College of Medicine students, residents, full-time faculty, and clerkship directors. Mobile friendly. App available.

USPSTF Preventative TaskForce
Electronic Preventive Services Selector: search and browse U.S. Preventive Services Task Force (USPSTF) recommendations and guidelines. App available.

PICO: Form a Focused Clinical Question