How to Search Medical Databases

Practicing PAs
Written By Anne
 
 
 

A medical database is an organized collection of medical and healthcare-related information that is stored and made accessible through electronic means. These databases serve as repositories of vast amounts of medical literature, research articles, clinical data, patient records, and other healthcare-related information. They are essential tools for healthcare professionals, researchers, and students seeking evidence-based information, conducting research, and making informed clinical decisions.

Medical databases typically cover a wide range of medical topics, including various medical specialties, diseases, treatments, pharmacology, and public health. They may contain information from scientific journals, clinical trials, case studies, systematic reviews, medical textbooks, and more.

Here we’ll provide an overview of medical databases, how to search databases effectively, use of filters and evaluate your research results to discern relevant and high quality studies.

 

I. Overview of Medical Databases

a) Purposes of Databases

The primary purpose of medical databases is to provide a centralized and easily accessible source of credible and up-to-date medical information. These databases are invaluable for staying updated with the latest research, exploring evidence-based guidelines, and supporting evidence-driven clinical practice. Many medical databases also offer search and filtering tools to help users find relevant and specific information efficiently.

PubMed, Embase, MEDLINE, Scopus, Web of Science, and Cochrane Library are examples of well-known medical databases.

You can check with your PA program health sciences library guide to see if you have unlimited access to papers that link from those databases.

b) Select the Appropriate Medical Database

Each of these databases presents unique strengths, and familiarizing yourself with their features will enable you to make well-informed decisions on which to use for your research:

  • PubMed: PubMed is a widely-used, free medical database focused on biomedical and life sciences literature, including articles from scientific journals, clinical trials, and systematic reviews. It offers advanced search options and is a valuable resource for healthcare professionals and researchers seeking comprehensive medical literature.

    • Use PubMed for comprehensive biomedical literature and clinical studies. It is suitable for most medical research and evidence-based practice needs.

    • Click here to view PubMED Video Tutorials

  • Embase: Embase is a biomedical database renowned for its coverage of drug research, pharmacology, and pharmaceutical information, making it useful for pharmacovigilance and evidence-based medicine. It complements PubMed for comprehensive literature searches.

    • Use Embase when conducting drug-related research, pharmacovigilance, and pharmaceutical literature searches.

  • MEDLINE: MEDLINE, a component of PubMed, is a respected bibliographic database for life sciences, offering extensive coverage of medical research articles from thousands of journals.

    • MEDLINE is part of PubMed, so use PubMed for accessing MEDLINE content.

  • Scopus: Scopus is a multidisciplinary citation database covering various scientific fields, including medical, social sciences, and engineering, making it valuable for interdisciplinary research.

    • Use Scopus or Web of Science when conducting interdisciplinary research and tracking research impact across multiple fields.

  • Web of Science: Web of Science is another multidisciplinary citation database offering citation indexing and analysis for tracking research impact and influential articles beyond medical fields.

  • Cochrane Library: Cochrane Library is a specialized database focusing on evidence-based medicine, housing systematic reviews and meta-analyses, crucial for evidence-driven clinical decision-making by healthcare professionals.

    • Use Cochrane Library when seeking evidence from systematic reviews and meta-analyses for specific medical interventions or treatments.

 

II. Constructing the Search Terms using PubMed

Step 1) Formulate your Research Question

Begin by identifying the main concepts of your research question. These are the key elements that define your topic.

 

Example Research Question:
What is the effectiveness of a new diabetes medication in reducing blood glucose levels in elderly patients?

Main Concepts from this Research Question:
"diabetes," "medication," and "elderly patients."

 

Step 2) Identify Relevant Keywords and Synonyms for Each Concept: This includes synonyms and related terms. This comprehensive keyword list will form the foundation of your search strategy.

 

Concept 1: New Diabetes Medication Keywords: New diabetes medication, novel antidiabetic drug, latest diabetic drug, experimental diabetes treatment

Concept 2: Reducing Blood Glucose Levels Keywords: Reducing blood glucose, lowering blood sugar, glycemic control, blood glucose management

Concept 3: Elderly Patients Keywords: Elderly patients, older adults, geriatric population, seniors

 

Step 3) Conduct your Initial Search

Before doing your initial search:

  • Eliminate Filler Words: Many search engines automatically ignore common filler words like "the," "and," "in," etc. When searching in PubMed, there's no need to worry about eliminating filler words as PubMed automatically ignores them.

  • Boolean Operators: Combine your search terms using BOOLEAN operators (AND, OR, NOT). Use:

    • "AND" to narrow results by requiring all search terms to appear in the documents retrieved.

    • "OR" broadens results, retrieving documents containing any of the search terms.

    • "NOT" helps exclude specific terms, refining your search further.

  • Phrase Search: To find exact phrases, enclose them in quotation marks (e.g., "diabetes management"). This ensures the search engine looks for the exact phrase rather than individual words

  • Wildcards: Wildcards (e.g., , ?) can be used to represent unknown characters or variations of a word, expanding your search scope. For example, "wom?n" would retrieve both "woman" and "women." or behavio?r includes behaviour and behavior.

  • Truncation: Truncation involves adding a symbol (usually an asterisk* ). to the end of a word stem to capture multiple word endings or variations. hen you use truncation, PubMed will retrieve results that include any term starting with the specified word stem. For example, searching for "child*" will retrieve articles containing words like "child," "children," "childhood," etc.

Start by entering your search query into the PubMed search bar and click the "Search" button. You will be presented with a list of search results related to your query.

 

PubMed Search Inquiry:
("diabetes medication" OR “nove antidiatbetic drug” OR “new diabetes medication” or “experimental diabetes treatment” OR "antidiabetic drugs" OR "diabetic drug*") AND (“reducing blood glucose” OR “lowering blood sugar” OR “glycemic control” OR “blood glucose management” OR "blood glucose levels" OR "blood sugar levels") AND (elderly OR geriatric OR senior*)

Explanation of the Search Query:

  • Phrase Search: We used the phrase search by enclosing the exact phrases within double quotation marks. For example, "diabetes medication" ensures that PubMed looks for the exact phrase "diabetes medication" in the search results.

  • Wildcards: We used the wildcard * to represent word variations. For example, "diabetic drug*" will retrieve articles with terms like "diabetic drugs," "diabetic drug therapies," "diabetic drug treatment," and so on.

  • Truncation: We used truncation for the term "senior*," which captures multiple word endings related to "senior" such as "seniors," "seniority," and "senior citizen."

  • Boolean Operators:

    • We used "OR" to broaden the results for synonyms and related terms within each main concept. For example, "diabetes medication" OR "antidiabetic drugs" OR "diabetic drug*" will retrieve articles containing any of these terms.

    • We used "AND" to narrow the results by requiring all three main concepts to appear in the articles retrieved. For example, ("diabetes medication" OR "antidiabetic drugs" OR "diabetic drug*") AND ("blood glucose levels" OR "blood sugar levels") AND (elderly OR geriatric OR senior*) will retrieve articles that contain at least one term from each set of parentheses.

 

Step 4) Refine your Search

  • Filters: Locate the Filters Sidebar, and choose filters relevant to your search. Once you have selected the filters you want to use, click on the checkboxes beside each filter to activate them. If you find that your search results are too limited, consider adjusting or removing some filters to broaden your search. Similarly, if you have too many results, adding more filters or narrowing the publication date range may help focus your results. Common filters in PubMed include:

    • Publication Date: Limit your search results to articles published within a specific time range. This allows you to focus on the most recent research.

    • Article Types: Select specific types of articles, such as clinical trials, reviews, case reports, or meta-analyses, depending on the nature of your research question.

    • Study Types: Choose study types like randomized controlled trials (RCTs) or cohort studies to narrow your results to specific study designs.

    • Languages: If you prefer articles in a specific language, you can select it as a filter.

    • Journal Categories: Limit your results to articles published in specific journal categories (e.g., clinical medicine, biochemistry, pharmacology).

  • MesH and ATM: PubMed uses Medical Subject Headings (MeSH) to index articles. Utilize MeSH terms to refine your search further and ensure comprehensive results. When you enter keywords, PubMed automatically maps them to MeSH terms using Automatic Term Mapping (ATM). Review the MeSH terms used for your search and select them to include in your search strategy if appropriate.

Step 5) Save or Share your Filtered Search

To save your search, you would have to create an NBI Account. Once created, login.

  • Save Individual Articles: After performing a search in PubMed and finding a relevant article, click on the article's title to view the abstract and full text (if available). On the right side of the abstract page, you'll see a box labeled "Save." Click on the arrow next to it to display options, then select "Collections."

  • Create a Collection: If you haven't created a collection before, you'll be prompted to create one. Give your collection a name that reflects the topic or purpose, and click "Save." If you've already created collections, you can choose an existing collection from the list.

  • Add the Article to the Collection: Once you've selected or created a collection, click "Add to Collections" to save the article in that collection.

  • Access Saved Articles: To access your saved articles and collections, click on the "My NCBI" link at the top right corner of the PubMed page, and then select "Collections" from the drop-down menu. You'll see a list of your collections and the articles saved in each one.

  • Set Up Email Alerts: In addition to saving individual articles, you can also set up email alerts to receive notifications when new articles matching your search criteria are published. To do this, perform your desired search in PubMed, then click the "Create alert" link located below the search bar. Follow the prompts to name your alert and choose the frequency of email updates (daily, weekly, or monthly).

  • Manage Your Collections and Alerts: From the "Collections" and "Saved Searches" pages within My NCBI, you can manage your saved articles and alerts. You can add or remove articles from collections, edit collection names, modify email alert settings, or delete alerts if you no longer wish to receive them.

 

III. Example PubMed Search Inquiries with Breakdown

Here are additional examples of research questions broken down into PubMed Search Inquiries:

  • Step 1) Formulate your Research Question:

    • Research Question:
      How do physician assistants reduce wait times in the emergency department?

    Step 2) Identify relevant keywords or synonyms from each concept:

    • Concept 1: Physician Assistants; Keywords: Physician assistants, PA, advanced practice providers, physician associates

    • Concept 2: Reduce Wait Times; Keywords: Reduce, decrease, minimize, shorten, alleviate, waiting times, waiting periods, patient flow, throughput

    • Concept 3: Emergency Department; Keywords: Emergency department, ED, emergency room, ER, urgent care center, acute care facility

    Step 3) Conduct your initial search with boolean operators, phrase search, wildcards, and truncation:

    • Sample PubMed Search Query
      (physician assistant* OR PA OR "advanced practice providers" OR "physician associate*") AND (reduce OR decrease OR minimize OR shorten OR alleviate OR "waiting times" OR "waiting periods" OR "patient flow" OR throughput) AND ("emergency department" OR ED OR "emergency room" OR ER OR "urgent care center" OR "acute care facility")

    Explanation of the Search Query:

    • Boolean Operators:

      • We used "OR" to include synonyms or related terms for each main concept. For example, (physician assistant OR PA OR "advanced practice providers" OR "physician associate") will retrieve articles containing any of these terms related to physician assistants.

      • We used "AND" to narrow the results by requiring all three main concepts to appear in the articles retrieved. For example, (physician assistant OR PA OR "advanced practice providers" OR "medical extenders") AND (reduce OR decrease OR minimize OR shorten OR alleviate OR "waiting times" OR "waiting periods" OR "patient flow" OR throughput) AND ("emergency department" OR ED OR "emergency room" OR ER OR "urgent care center" OR "acute care facility") will retrieve articles that contain at least one term from each set of parentheses.

    • Phrase Search: We used phrase search by enclosing exact phrases within double quotation marks. For example, "waiting times" ensures PubMed looks for the exact phrase "waiting times" in the search results.

    • Wildcards: We used wildcards for physician assistant* to include “physician assistants”

    • Truncation: We didn't use truncation in this example, but it could be used for terms like "reduce" or "waiting" to capture multiple word endings or variations.

  • Step 1) Formulate your Research Question:

    • Research Question: What is the impact of exercise without medications on lowering blood pressure?

    Step 2) Identify relevant keywords or synonyms from each concept:

    • Concept 1: Exercise
      Keywords: Exercise, physical activity, aerobic exercise, resistance training, fitness, workout

    • Concept 2: Without Medications
      Keywords: Without medications, non-pharmacological, lifestyle intervention, drug-free, natural intervention

    • Concept 3: Lowering Blood Pressure
      Keywords: Lowering blood pressure, reducing hypertension, blood pressure management, hypertensive patients, antihypertensive effects

    Step 3) Conduct your initial search with boolean operators, phrase search, wildcards, and truncation:

    Sample PubMed Search Query:

    (exercise OR "physical activity" OR "aerobic exercise" OR "resistance training" OR fitness OR workout) AND ("without medications" OR "non-pharmacological" OR "lifestyle intervention" OR "drug-free" OR "natural intervention") AND ("lowering blood pressure" OR "reducing hypertension" OR "blood pressure management" OR "hypertensive patients" OR "antihypertensive effects")

    Explanation of the Search Query:

    • Boolean Operators:

      • We used "OR" to include synonyms or related terms for each concept. For example, (exercise OR "physical activity" OR "aerobic exercise" OR "resistance training" OR fitness OR workout) will retrieve articles containing any of these terms related to exercise

      • We used "AND" to narrow the results by requiring all three main concepts to appear in the articles retrieved. For example, (exercise OR "physical activity" OR "aerobic exercise" OR "resistance training" OR fitness OR workout) AND ("without medications" OR "non-pharmacological" OR "lifestyle intervention" OR "drug-free" OR "natural intervention") AND ("lowering blood pressure" OR "reducing hypertension" OR "blood pressure management" OR "hypertensive patients" OR "antihypertensive effects") will retrieve articles that contain at least one term from each set of parentheses.

    Phrase Search: We used phrase search by enclosing exact phrases within double quotation marks. For example, "physical activity" ensures PubMed looks for the exact phrase "physical activity" in the search results.

    Wildcards: We didn't use wildcards in this example, but they can be used to represent word variations. For example, "exercis*" would retrieve articles with terms like "exercise," "exercises," "exercising," etc.

    Truncation: We didn't use truncation in this example, but it could be used for terms like "lowering" to capture multiple word endings or variations.

  • Step 1) Formulate your Research Question:

    Research Question:
    What is the effectiveness of Cognitive Behavioral Therapy for anxiety disorders?

    Step 2) Identify relevant keywords or synonyms from each concept:

    • Concept 1: Cognitive Behavioral Therapy
      Keywords: Cognitive Behavioral Therapy, CBT, cognitive therapy, behavior therapy, cognitive-behavioral interventions

    • Concept 2: Anxiety Disorders
      Keywords: Anxiety disorders, generalized anxiety disorder, social anxiety disorder, panic disorder, phobias, anxiety conditions

    Step 3) Conduct your initial search with boolean operators, phrase search, wildcards, and truncation:

    Sample PubMed Search Query:
    ("Cognitive Behavioral Therapy" OR CBT OR "cognitive therapy" OR "behavior therapy" OR "cognitive-behavioral interventions") AND ("anxiety disorders" OR "generalized anxiety disorder" OR "social anxiety disorder" OR "panic disorder" OR phobias OR "anxiety conditions")

    Explanation of the Search Query:

    • Boolean Operators:

      • We used "OR" to include synonyms or related terms for each concept. For example, ("Cognitive Behavioral Therapy" OR CBT OR "cognitive therapy" OR "behavior therapy" OR "cognitive-behavioral interventions") will retrieve articles containing any of these terms related to Cognitive Behavioral Therapy.

      • We used "AND" to narrow the results by requiring both main concepts to appear in the articles retrieved. For example, ("Cognitive Behavioral Therapy" OR CBT OR "cognitive therapy" OR "behavior therapy" OR "cognitive-behavioral interventions") AND ("anxiety disorders" OR "generalized anxiety disorder" OR "social anxiety disorder" OR "panic disorder" OR phobias OR "anxiety conditions") will retrieve articles that contain terms from both sets of parentheses.

    • Phrase Search: We used phrase search by enclosing exact phrases within double quotation marks. For example, "Cognitive Behavioral Therapy" ensures PubMed looks for the exact phrase "Cognitive Behavioral Therapy" in the search results.

    • Wildcards: We didn't use wildcards in this example, but they can be used to represent word variations. For example, "therap*" would retrieve articles with terms like "therapy," "therapies," "therapeutic," etc.

 

Final notes

By formulating well-defined research questions and identifying relevant keywords, one can lay a strong foundation for conducting comprehensive literature searches. Through the strategic use of boolean operators, phrase searches, wildcards, and truncation, researchers can fine-tune their searches, ensuring they obtain relevant and valuable information from databases like PubMed.

Moreover, mastering the use of filters and search tools in databases allows researchers to limit search results, save searches, and receive updates on new relevant literature, streamlining the process of staying up-to-date with the latest medical research.

 

References

Anne

I am a Canadian trained and certified Physician Assistant working in Orthopaedic Surgery. I founded the Canadian PA blog as a way to raise awareness about the role and impact on the health care system.

http://canadianpa.ca
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