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Library Resources for your BMEN 604

PICO is a framework for formulating research questions that is often used by researchers planning a systematic review. It helps to focus your topic, and clarifies what is included in your study, and what is excluded. PICO (or sometimes PICOS) stands for:

First, determine what type of question you are asking. Different questions may require different study designs. Common types of questions include therapy (does therapy A work for problem B); risk or harm (does exposure to A directly cause or raise people's risk of B); and diagnosis (Can text A correctly diagnose condition B). 

  • P - patient/problem/population: indicate here relevant information about your population of interest, including their disease or health issue, and info about age, gender, other demographic variables that may be relevant.
  • I (or sometimes E) - the intervention or exposure of interest. This could be a drug or device for therapy questions, an exposure to a harmful substance or experience for a harms or risk question, or a diagnostic test or screening instrument for a diagnosis question.
  • C - comparison: often you will be comparing your intervention of interest to something else - either a current gold standard, or a placebo. Sometimes there will be no comparison, and you can leave this blank.
  • O - outcome(s) of interest. What is the study trying to find out, and how will it be measured? Morbidity/mortality/clinical results may be used for therapy studies, sensitivity and specificity for diagnostic tests, and defined adverse effects for a risk or harms study.
  • S - study design (optional). Think about the study designs you are interested in. Often for a therapy question, these will be randomized controlled trials, but may also include qualitative studies. For a diagnosis study, they may be RCTs that assess sensitivity and specificity. For a harms or risk study, it is unethical to conduct an RCT, and you may need to look at observational studies. You may or may not choose to specify a study design.

Often one of the above elements will be unknown, but you generally need to have two of them well defined in order to search the literature. Some PICO elements may not be things you search the literature on, but they inform your inclusion/exclusion criteria for what literature you want to consider.

Example question: For patients with Type I diabetes, how does conventional insulin delivery (multiple daily injections, often abbreviated MI) compare to continuous subcutaneous insulin infusion (CSII) via an insulin pump, for glycemic control? 

Here's how we would map this question to PICO. Include any synonyms or acronyms you can think of; these become search terms

P - Type I diabetes OR  juvenile diabetes; all ages (we don't search by age group, as we're interested in everyone)

I - insulin injections or multiple daily injections or multiple injections or MI

C - continuous subcutaneous insulin infusion OR CSII OR insulin pump

O - glycemic control (may or may not want to specify specific measures of this)

- randomized controlled trials (RCTs)

 The terms in red become search terms for PubMed and other databases. Age groups are not searched because we are interested in all ages. Glycemic control is not searched, because it's probably the main outcome of interest in all of these studies; if not, then it can just be used to determine whether or not the article is of interest. RCTs are not searched, but again, good to keep in mind when thinking about whether a study is relevant to you. 

Let's try one together. Access the Google Jamboard.

Book Collections:

The collections below have many common Engineering textbooks and handbooks, but they also go beyond books and offer chemical and material data and property search tools, equations, and videos.

You can also search the main library web site for books by exact title, or by keyword phrase (example, "cardiac devices" and then use the menu on the left to limit to books and book chapters:

Database search tips:

Example search: the tips below discuss the following example, using SportDiscus, but they can be applied to other databases. Here, I am interested in finding literature on the effect of barefoot running shoes, also sometimes called minimal or minimalist footwear, are effective for gait retraining.

  • Some databases are "smart" enough to understand your search, analyze it for synonyms and related terms, etc. But many are not; they only look for what you put in. Spelling mistakes will not be corrected. Acronyms will not be spelled out. You need to think of all relevant key terms.
  • Many databases let you add boxes, which makes it easy to put one concept in each box, along with all its synonyms. So for example, "minimalist or barefoot", then "shoes or footwear or sneakers"
  • An asterisk on the end of a word searches for all words that begin with that stem - so shoe* finds shoe, shoes, shoehorn, etc. Be careful! A search for can* will find cancer, but also cannon, canvas, cannabis, etc. You need a unique "stem" to avoid this problem.
  • Put quotation marks around a phrase to let the database know to search for this exact phrase. For example, "gait retraining." 


Database Searching Tutorials

The resources below all review the literature in some way to provide guidelines for practitioners or policy makers. 

Clinical practice guidelines are written by medical associations to summarize the literature on common problems and questions.

Systematic Reviews are more thorough and rigorous than a regular literature review. They attempt to find and synthesize all evidence around a specific question, and come up with recommendations. 

  • Cochrane Database of Systematic Reviews includes all current reviews published by the Cochrane Collaboration, an international collaboration of evidence-based medicine. Note that Cochrane Reviews are also indexed in PubMed
  • You can limit to systematic reviews in PubMed using the filters on the left-hand side of the results page.

Health Technology Assessments review specific drugs or devices, and may include an economic or policy assessment. HTAs are often published on government or organization web sites, but not in the peer reviewed literature. They are considered "grey" literature.