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EBP & PICOT Questions

Background for Research Design and Publication Types

Broad Study Types


· Generate numerical data or data that can be converted into numbers. 

· Can sort out

· Can be an empirical article when its methodology describes original research (i.e., not a review article)











Terms for Searching/Search Strategies:


Examples of quantitative studies:

Case report - report on a single patient;
Case series - report on a series of patients (no control group);
Case control study - identifies patients with a particular outcome (cases) and control patients without the outcome. Looks back and explores exposures and possible links to outcome. Very useful in causation research;
Cohort study - identifies two groups (cohorts) of patients one which received the exposure of interest, and one which did not. Follows these cohorts forward for the outcome of interest. Very useful in causation as well as prognosis research. (Bandolier 2004)
Randomized Controlled Trial (RCT) - a clinical trial in which participants are randomly allocated to a test treatment and a control; involves concurrent enrollment and follow-up of both groups; gold standard in testing the efficacy of an intervention (therapy/prevention); RCTs are 
experimental literature ("primary literature in which the experimenter controls exposures that the subjects have")
Systematic Review - identifies and critically appraises all research on a specific topic, and combines valid studies; increasingly important in evidence based medicine; different from review article (which is a summary of more than one paper on a specific topic, and which may or may not be comprehensive)
• Meta-Analysis - a systematic review that uses quantitative methods to summarize the results.
(Bandolier 2004; NCBI 2010)
Cross-sectional survey - the observation of a defined population at a single point in time or time interval. Exposure and outcome are determined simultaneously. Gold standard in diagnosis and screening research;
Decision analysis - uses the results of primary studies to generate probability trees to be used in making choices about clinical management or resource allocation;
Economic analysis - uses the results of primary studies to say whether a particular course of action is a good use of resources. (Bandolier 2004; Greenhalgh 2001)


· Generate
non-numerical data (text/classes fields).

Can sort out WHY and HOW

· Explore and understand people's beliefs, experiences, attitudes, behavior and interactions.

· Can be an empirical article when its methodology describes original research (i.e., not a review article)


(qualitative OR ethnograph* OR phenomenolog* OR "grounded studies" OR "case studies" OR "narrative studies" OR "focus groups")

Examples of qualitative studies:
• Document - study of documentary accounts of events, such as meetings;
• Passive observation - systematic watching of behavior and talk in natural occurring settings;
• Participant observation - observation in which the researcher also occupies a role or part in the setting, in addition to observing;
• In depth interview - face to face conversation with the purpose of exploring issues or topics in detail. Does not use preset questions, but is shaped by a defined set of topics;
• Focus group - method of group interview which explicitly includes and uses the group interaction to generate data. (Greenhalgh 2002). 
Adapted from:

Gehlbach, S. H. (2002). Interpreting the medical literature. McGraw-Hill.