Evidence Based Medicine

Do I have to form a question?

It is highly recommended to frame your research in the form of a question. This helps you stay focused in your searching and only gather the information you need to accurately and thoroughly answer the research question.

Creating and searching a question is an iterative and exploratory process. You may have an idea of what you want to research, but it takes some time to determine a precise, searchable question.

1. Do your backgorund research to inform yourself of what's already been published in the literature
2. Formulate a basic question based on your background knowledge
3. Go fishing in a couple of representative databases to see what you find (eg PubMed and Web of Knowledge)
   1. Was my topic too broad? Too narrow?
   2. What terms and phrases are used in the published literature?
   3. What aspects of the research am I truly interested in?

After doing a preliminary search of the literature and honing your interests, you can then form a specific, searchable question.

Framing your search in the form of a precise question allows you to clarify the criteria needed for selecting relevant studies. An example question for research might be: Have laws limiting soda sales decreased rates of obesity in children?

In clinical medicine, one technique for creating a searchable question is to put it in the form of a PICO question.

• P: Population or Problem
• I: Intervention
• C: Comparison
• O: Outcome

We could form a PICO from our previous question about childhood obesity and soda laws:

• P: Children
• I: Laws limiting soda
• C:
• O: Obesity

Not all questions are comparing two treatments or interventions, so it is possible to follow a PICO and not include a comparison.

Once you execute a search, it may be that you do not find anything that answers your question. This can lead to either thinking of new or more terms to represent your PICO elements, or reframing your search question entirely. Research -whether bench, clinical or literature - is an iterative process.

PICO may not specifically apply to your research question, but the principle of breaking your question into searchable chunks still applies.

Different databases require different search strategies. Some have controlled vocabularies, while others are keyword-based; but all databases are more easily searched if you think of the terms that represent each idea in yourquestion prior to searching.

In a systematic review, you are required to search databases that use both controlled vocabularies and keywords. Setting up a simple chart like the pone below can help you stay organized in your searching. Create a column to represent each idea and two rows beneath. One row is to generate the controlled vocabulary terms that describe the topic, while the other are all of the synonyms and phrases to express the idea in a keyword search. terms within a column will typically be combined with OR, while different columns will be combined with AND.

Multiple charts might be made throughout a Systematic Review; perhaps one for each database searched, or a new iteration if terms were added or removed from a different iteration of the search later in the study.