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Public Health

Comprehensive guide to library and open resources that support Purdue students, staff, and faculty with Public Health research and publication.

Research Basics

  • Step One: What is your research question, if you can easily explain what you are researching in a one sentence question, you will have a much easier time finding relevant resources.
    • What type of intervention should be used to increase physical activity in adolescents according to the theory of triadic influence?


  • Step Two: Don't search for the whole question, instead focus on the important parts of the question
    • theory of triadic influence
    • physical activity
    • adolescents


  • Step Three: Choose the best database/s for your research question
    • The Family and Community Health, Environmental Health, and Health Statistics pages have recommended databases to use for those subject areas.
      • Searching the databases allows you to find the original research and review articles needed for evidence based decision making
    • Wikipedia (and other similar resources) are great for providing background understanding of new terms and concepts, but rarely should these resources be used for class assignments.
      • If you find information in a Wikipedia article that you want to use for an assignment, check if the article links to a more authoritative resource, like a scholarly article or professional organization webpage.


  • Step Four: Search the database
    • Take your key concepts and combine them to search.
    • Using the above example you would search "Theory of triadic influence" AND "physical activity" AND adolescents 
      • I have quotes around my phrases so that the database will search for that exact phrase otherwise it looks for each word within the article but not necessarily together which can increase the number of false hits.
    • Keep in mind you may have to use some trial and error to find the best terms to use
      • For instance, you may also want to search exercise OR "physical activity"


  • Step Five: After you run your search, check to see that the database is showing the most relevant resources first
    • Also look to see if there are limiters/filters that are appropriate for your search
      • Using our example search instead of using the keyword term adolescents, I can look for a filter based on age to limit my results to a specific age range


  • Step Six: Reviewing the results for appropriate articles
    • If your search returns too many results you may want to add additional concepts to your search.
      • For instance I might add the term intervention to my search ("Theory of triadic influence" AND "physical activity"  AND intervention)
    • Keep in mind when reviewing articles that not everyone is going to fit the parameters of your research question.
      • A common example is when searching for intervention studies, the key concept to keep in mind whether the researchers actually performed an intervention (did they do something) or are they talking about proposed interventions or surveying their population in preparation for performing an intervention. 
      • One good way of telling whether or not a study was an intervention is to look for a methods section. In that section the authors should explain exactly what they did. Again, this is not perfect because they may not have a specific methods section or they might be describing their survey.


  • If you find a good article and you see a message saying full text is not available, don't forget that you can request the article using Interlibrary Loan.
    • This is a free service and most articles arrive within a couple of days as a pdf file
  • When you use ideas from any source as part of your course assignments, you must cite the original content according to the citation style assigned by your instructor.
    • Check out the AMA style tab for help using AMA
  • At any point in the research process you can contact me for help!

Boolean Searching

Boolean terms give you more control of your search. Used correctly they can save time by returning more relevant articles


  • AND narrows a search by requiring each term to appear in the result ( a Google search automatically buts AND between each word you type)
    • for example if you wanted results about football players dealing with a concussion you might search football AND concussion
    • Doing an AND search will reduce the number of results you get
  • OR broadens a search, allowing you to search for similar terms
    • For example you could search ACL or Anterior Cruciate Ligament
    • This will increase the number of results you get from a search
    • This strategy is good if your original search didn't return any useful articles
  • NOT removes a term from consideration. This means if an article a term you don't want that article will not show up, even if the words you do want appear.
    • For example if you get a lot of animal studies you could say NOT rats 
    • This will narrow your search and should only be used in rare situations

General Library Resources

Interlibrary Loan (ILL): is a service provided free of charge to Purdue students, staff, and faculty. Many of our databases have an icon called "Find It @ Purdue Libraries" that you can click to check if we have the full text or access to that resource. If we do not have full text, you will see an option to "Request via Interlibrary Loan". For articles requests are generally completed within 2 business days, while physical items will take longer depending on how far away the lending library is. Please note, textbooks cannot be requested through this service.