THL Evidence-Based Practice

We will use the foreground question in the 1. ASK a Question step of the 5As EBP Process as the building blocks of our search strategy.

To develop the search strategy from this foreground question, we will identify the unique concepts in the question. If you have applied a question framework, such as PICO, the elements in the framework are a great place to start.

In pediatric patients with asthma, does RSV infection compared to no infection impact admission to the ICU?

P (Patient, population, or problem): pediatric patients with asthma
I (Intervention, exposure, or test): RSV infection
C (Comparison): no infection
O (Outcome): admission to the ICU

The unique concepts in this search are pediatric, asthma, RSV infection, and ICU admission. 

For each unique concept it is often helpful to brainstorm synonyms or related terms.  This step is helpful for finding literature that is relevant to our question but using slightly different language than we originally thought of. We can organize our synonyms and related terms in tables. 

For this type of information search It's not necessary to find all synonyms for each term, but investing time in developing a few can improve the search results. Here we demonstrate the idea behind considering various versions of our population concept words. While "infection" and  "admission" were identified as part of the RSV and ICU-portions of each concept respectively, we might try focusing on the RSV and ICU parts first. Searching requires testing out different approaches. In this instance, we should be prepared to adjust our terms and iterate. 

The next step is to use Boolean logic to combine our search terms and concepts.

First we will combine the synonyms and related terms using OR. Next we place parentheses around each concept group. Then we will combine all four concept with AND. This will allow us to find articles at the intersection of the four concepts. 

(pediatric OR pediatrics OR child OR children OR infant OR infants)

AND

(asthma OR difficulty breathing OR wheezing OR airway hypersensitivity)

AND 

(RSV OR respiratory syncytial virus)

AND

(ICU OR intensive care unit OR critical care unit)

Searching common phrases like intensive care unit as a phrase using double quotation marks may improve the relevance of the results. For each common phrase in the search strategy we are developing, we have added double quotation marks around the phrase.

(pediatric OR pediatrics OR child OR children OR infant OR infants)

AND

(asthma OR "difficulty breathing" OR wheezing OR "airway hypersensitivity")

AND 

(RSV OR "respiratory syncytial virus")

AND

(ICU OR "intensive care unit" OR "critical care unit")

For this search on RSV infection in a pediatric population, we will search for literature in the database PubMed and apply filters that are available in that database. 

PubMed provides several article type filters that can be applied to your search results. These filters are located on the left side of the results page after you have executed a search. Not all of the available filters appear by default. Click on "Additional filters" to see and select filters, click "Show" to show them on the results page. From the results page, click the desired filter(s) to apply them. The "Levels of Evidence" box below provides an overview of the Evidence Pyramid and definitions of various study designs to consider in your filter selection. Here we show a portion of the results page in PubMed for our search on RSV infection. The article type filters "Randomized Controlled Trial" and "Systematic Review"  are selected. With these filters applied, PubMed will return results matching our search terms that are either randomized controlled trials or systematic reviews. 

Note: Filters vary by database. For help selecting an appropriate database for your topic and for using its features and tools, contact us at thlibrary@umich.edu.

Primary vs. Secondary Literature