NSG422: Nursing Research: Evidence-Based Practice

Formulating Answerable Clinical Questions is the Foundation of EBP!

Every time we see a patient, we need new information about some element of the diagnosis, prognosis or management. Because our time to try to find this information is often limited, we need to be very efficient in our searching. To achieve this efficiency, we need to become skilled at formulating clinical questions.

1. Start with the patient: clinical problems and questions arise out of patient care
2. Translate the clinical questions into a searchable question using PICOT
3. Decide on the best type of study to address the question
4. Perform a literature search in the appropriate source(s)

Is your clinical question answerable?

• "What is the best treatment for recurrent UTI in children?" is so broad that a meaningful answer is difficult to find due to the large number of articles you may retrieve addressing many possible treatments and clinical outcomes. 
• "In children with recurrent UTI, is cranberry juice effective in reducing the number of recurrences?" is more focused and will lead to a doable search strategy. 

Express your clinical question in the PICO format

• P - Patient or Population AND Problem
• I - Intervention: a treatment, a diagnostic test, an exposure to a known or presumed risk factor, etc.
• C - Comparison: treatment, placebo, gold standard diagnostic test, absence of risk factor, etc. 
• O - Clinical outcome of interest
• T - Time frame it should take you to determine whether your interventions had any affect or Type of Question Asked

The PICOT terms come from and should match your clinical question. 

As you move down this list, the study designs are less rigorous and allow for more bias or systematic error that may distract you from the truth. 

1. A Meta-Analysis is a statistical technique for combining the findings from independent studies to assess the clinical effectiveness of healthcare interventions.
2. A Systematic Review is a comprehensive, unbiased review of multiple research studies that tries to identify, appraise, select and synthesize all high quality research evidence relevant to that research question.
3. A Random Control Trial (RCT) is an experiment that delivers an intervention or treatment; subjects are randomly assigned to control and experimental groups, so it is the strongest design to support cause and effect relationships.
4. A Cohort Study looks at groups of patients who are already taking a particular treatment or have an exposure; subjects are followed over time, and then outcomes are compared with a similar group that has not been affected by the treatment or exposure being studied. 
5. A Case Control Study looks at patients who already have a specific condition compared to people who do not have the condition. These studies rely on medical records and patient recall for data collection. 
6. Case Series and Case Reports consist of collections of reports on the treatment of individual patients or a report on a single patient. 
7. A Literature Review is a scholarly analysis of a body of research about a specific issue or topic.

Adapted from Duke Library's EBP Tutorial: Introduction to Evidence-Based Practice http://guides.mclibrary.duke.edu/c.php?g=158201&p=1036002

Your textbook covers the different clinical case studies used in evaluating and informing evidence-based practice. While not exhaustive, the most common case studies are: 

• Systematic Review & Meta-Analysis
• Randomized Controlled Studies or Trials
• Case Series / Case Reports
• Cohort Studies
• Double Blind

Review the following PowerPoint for an overview of each case study in a nutshell:

 Where you look for information is determined by what kind of question you are asking.  One way of classifying your question is to ask whether you are seeking background information or foreground information.

 Background information is sought when a learner has general clinical questions regarding a topic such as what is the disorder; what causes it; how does it present; what are some treatment options.  These questions can be answered by using "background" resources such as textbooks (both in print and electronic) and narrative reviews in journals which give a general overview of the topic. 

Foreground information answers specific questions a clinician has regarding a specific patient.  Foreground resources can be divided into primary sources such as original research articles published in journals; and secondary sources such as systematic reviews of the topic, and synopses and reviews of individual studies.

  Critical appraisal is a systematic process of analyzing research to assess methods, validity and usefulness. 

The key questions in critical appraisal are:

Why was the study done?

• A clearly focused question should address population, intervention and outcomes.

What type of study was done?

• The study design must match the question asked. Intervention questions are best answered with randomized controlled trials.

What are the study characteristics?

• Use the PICO question format to help you answer the question. 

What was done to address bias?

• Was the assignment of patients to treatments randomized?
• Were patients, health workers and study personnel ‘blind’ to treatment allocation? 
• Were all of the patients who entered the trial properly accounted for at its conclusion? Look for follow-up tables and whether patients were analyzed in the groups to which they were randomized. 
• Were the groups similar at the start of the study?
• Aside from the experimental intervention, were the groups treated equally?

What are the results and are the results valid?

• Are the outcome measures relevant?
• How large was the treatment effect? How precise was the estimate of the treatment effect?
• Look for confidence limits and p values.

What conclusions can you make?

• Are the results generalizable, that is, can the results be applied to my patients?  Were all clinically important outcomes considered? Are the benefits worth the harms and costs?
• Are the results relevant to my situation? Patient population / similar definitions/protocols/health system similarities.

Adapted from: Voutier, C. (2013). Critical appraisal. Evidence Direct: A Service of the RMH Health Sciences Library. Retrieved 17 December 2015 from: http://library.mh.org.au/index.php?option=com_content&view=article&id=272&Itemid=537