Evidence Based Practice: Searching for Evidence

  •   February 3, 2015
  •  Leanne Loranger, PT

So far, our series of articles on evidence based practice have addressed the importance of integrating research evidence (along with clinical experience and patient preference) into clinical practice  and has described how to formulate a PICO question. With that foundation beneath us, we now turn to the task of searching for the evidence. In fact, laying the ground work of a strong and effective PICO question will set you on a clear path to establishing your search terms.

Search Terms
Returning to our prior example of a fall prevention program for community dwelling females aged 65-90 who sustained a hip fracture from a fall within the last 12 months, you can build your search terms by combining the key components of the question and their synonyms. When looking for search terms, you may want to use as many synonyms as possible to the terms in your question in order to ensure that you find all the relevant research available. From there, you can narrow down what you actually review so you are not reading a mountain of information.

Population Invervention Control Outcome

- community dwelling
- females
- aged 65-90
- sustained a hip fracture within the last 12 months

-physiotherapist led
-eight week
-education and exercise

-no intervention

-fall rates
-repeat fracture rates

Search Terms: (Combine with OR) Search Terms: (Combine with AND) Limitors:  

Fall Prevention

- fall prevention

- accidental falls

- falls (keyword)

Fall Prevention AND Physiotherapy AND Exercise

- female

- Age: 65+

- Academic Journal

Using this search strategy, 42 potential articles were identified.

Adding the search term fracture narrowed the result to 1 study.


- physiotherapy

- physical therapy


- exercise

- group exercise

- theraputic exercise

In the example above, I chose to focus on some elements of the question, and left others out. In doing so I made a judgment that these were the most important components of the question.2 In real life, it may be the case that the post-fracture and fall prevention aspects of the question are most important. In that case a different set of search terms and synonyms should be chosen.

With the example chosen, we can see that if we further narrow our search by adding the term fracture, we end up with too few results. “The challenge is to try different combinations of the keywords to narrow the search (so as not to pull hundreds or thousands of articles), yet not narrowing it too much that important information could be missed.”2 By reviewing 42 abstracts to identify relevant research we are likely to identify a few articles with potential to answer our question. From this abstract review, we would hopefully identify a few studies to be read in full.

When considering search terms, you can also look to other articles that you have read to find relevant key words and subject headings for your topic. These keywords are used to index articles for online databases, and are often found at the end of the abstract. When you find a good article on your subject, you can also go through its reference list to see if you can identify other articles for review (commonly referred to as ‘hand searching’).

If after reviewing the abstracts found through your literature search you feel that your search did not identify relevant research, you may wish to go back and try some alternate search terms. For instance, you could search fall prevention, fractures and physiotherapy to see if that identified more relevant results. When it comes to search terms, the process really is one of trial and error. The good news is that the more regularly you engage in literature searching, the better you get at finding articles that relate to your area of interest.

Research Databases
Knowing what to search for is important, but it is also important to learn where to look. Knowing the databases where are you most likely to find relevant physiotherapy information will speed this process. Some favorites that come to mind are Pedro and Cinahl, and best of all, the Cochrane database. Cochrane is especially helpful as their systematic reviews and meta-analyses synthesize a large volume of research into one report, helping to identify the cumulative trends in research. By combining study results, (especially when considering several smaller studies), it is possible to achieve a more strongly powered, more generalizable and less biased conclusion that will guide your treatment plan than a single study can provide.3

One of the most frequently stated barriers to EBP is a lack of access to library resources. Getting access to research literature can be more challenging once you leave university, but it can be done! Here are some suggestions:

  • Check with your employer. Several large institutions have libraries on site and librarians on staff. My experience has been that when approached, these professionals are more than happy to help you conduct your searches.
  • Check with the UofA, if you take a student or help with a class you may be granted access to library resources for a period of time.
  • Become a member of your local library! Through your community library, you can access articles via The Alberta Library (TAL) using an interlibrary loan. These loans are often free of charge. Articles may also be available as an electronic copy, depending on licensing agreements, meaning that you may not even have to go to the library to pick up the reference you are looking for.
  • Canadian Physiotherapy Association (CPA) members have access to Physiotherapy Canada, the CPA’s own peer reviewed journal, in addition to access to EBSCO’s Rehabilitation Reference Center and OrthoEvidence which provide consolidated summaries of current evidence.

Google is another option but proceed with caution. While the internet has a treasure trove of information, ensuring that the information is credible can be challenging. One way to narrow your searching to more ‘reputable sites’ is to go to Google Scholar or use Google’s advanced search tools to search .edu or .gov sites to find more reliable sources of information. When gathering information online ask yourself a few questions about the source of that information:

  • Who is sponsoring the website? What are the author’s credentials?
  • Is the information provided referenced and verifiable?
  • Is the information presented in an unbiased manner?
  • Is there a commercial affiliation to the information/website?
  • When was the information posted or last revised?4

All of this information should be readily available or apparent on the website. The good news is that the current trend in research publication seems to be towards open access with even more information becoming accessible each week.

If your practice is built on one specific interest area, you may want to keep a lookout for open access journals on the subject or sign up for services that email you a regular update (RSS feeds,etc.) of articles published by the journal each month, making it easier for you to keep up with new developments. Two that I subscribe to are Spine and MedInfoNow both of which send me regular updates on recently published articles.

We’d love to hear your strategies for keeping up to date on research, and searching for information.  Discuss with your colleagues and then share your comments via email (lloranger@physiotherapyalberta.ca), Twitter (@PTAlberta) or Facebook.

The focus of the Evidence Based Practice series is to address questions and to create a dialogue between Physiotherapy Alberta and members of our profession, with the goal of facilitating evidence based practice and knowledge translation. Our intent is not to be the expert, but to be a knowledgeable voice in the conversation.


  1. Miller SA, Forrest JL. Ehancing your practice through evidence-based decision making: PICO, learning how to ask good questions. Journal of Evidence Based Dentistry Practice 2001; 1:136-141.
  2. Hastings C, Fisher CA. Searching for proof: Creating and using an actionable PICO question. Nursing Management 2014; August: 9-12.
  3. Mulrow CD. Systematic Reviews: Rationale for systematic reviews. BMJ 1994; 309: 597
  4. Law M, MacDermid J. Introduction to evidence-based practice. Evidence-based rehabilitation: A guide to practice. Thorofare: SLACK Incorporated. 2008.