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Health Studies

Welcome to the Library Research Guide for Health Studies. This guide will help you to find useful resources as you explore the field of Health Studies. It will also provide accurate, reliable sources as you write your research paper or projects.

Evidence Based Practice (EBP)

Evidence Based Practice (EBP) is an umbrella term for many different aspects of evidence based practice. EBP includes evidence-based medicine, evidence-based nursing, evidence-based physical therapy, evidence-based dentistry, etc.Evidence-Based Practice Triangle

Evidence-based practice (EBP) is the combination of

  • Clinical expertise
    The knowledge acquired through training and professional experiences
  • Evidence
    The best available information gathered from the scientific literature (external evidence) and from data and observations collected on your individual client (internal evidence)
  • Client/patient/caregiver perspectives
    The unique set of personal and cultural circumstances, values, priorities, and expectations identified by your client and their caregivers

When all three components of EBP are considered together, clinicians can make informed, evidence-based decisions and provide high-quality services reflecting the interests, values, needs, and choices of individuals with communication disorders.

AHSA. (n.d.). Evidence Based Practice (EBP). Retrieved from

Levels of Evidence Pyramid

The levels of evidence pyramid is a  way to visualize both the quality of evidence and the amount of evidence available. For example, systematic reviews are at the top of the pyramid, meaning they are both the highest level of evidence and the least common. As you go down the pyramid, the amount of evidence will increase as the quality of the evidence decreases.

Levels of Evidence Pyramid

Text alternative for Levels of Evidence Pyramid diagram

EBM Pyramid and EBM Page Generator, copyright 2006 Trustees of Dartmouth College and Yale University. All Rights Reserved. Produced by Jan Glover, David Izzo, Karen Odato and Lei Wang.

Levels of Evidence

The level of evidence can be defined by the type of question. Levels of evidence for a "Therapy" question are different from the levels of evidence for an "Etiology" question. 

Level of evidence (LOE)


Level I

Evidence from a systematic review or meta-analysis of all relevant RCTs (randomized controlled trial) or evidence-based clinical practice guidelines based on systematic reviews of RCTs or three or more RCTs of good quality that have similar results.

Level II

Evidence obtained from at least one well-designed RCT (e.g. large multi-site RCT).

Level III

Evidence obtained from well-designed controlled trials without randomization (i.e. quasi-experimental).

Level IV

Evidence from well-designed case-control or cohort studies.

Level V

Evidence from systematic reviews of descriptive and qualitative studies (meta-synthesis).

Level VI

Evidence from a single descriptive or qualitative study.

Level VII

Evidence from the opinion of authorities and/or reports of expert committees.

The table above is based on the following: Ackley, B. J., Swan, B. A., Ladwig, G., & Tucker, S. (2008). Evidence-based nursing care guidelines: Medical-surgical interventions. (p. 7)St. Louis, MO: Mosby Elsevier.

Research Study Designs and Forming Questions

Focus your question:

Use the PICO(T) model to help inform your research question.

What type of clinical question are you considering? What is the best study design to answer this type of question?

Clinical Question


Suggested Research Design(s)

All Clinical Questions

Questions look at all of the studies on a topic based on the inclusion and exclusion criteria.

Systematic review, meta-analysis


Questions look at the effectiveness of interventions in improving outcomes in sick patients/patients suffering from some condition. Most frequently asked type of question. 

Randomized controlled trial (RCT), meta-analysis Also: cohort study, case-control study, case series


Questions about the harmful effect of an intervention or exposure on a patient.

Randomized controlled trial (RCT), meta-analysis, cohort study

Also: case-control study, case series


Questions look at the ability of a test or procedure to differentiate between those with and without a condition or disease. 

Randomized controlled trial (RCT) 
Also: cohort study


Questions examine the effectiveness of an intervention or exposure in preventing morbidity and mortality. When assessing preventative measures, it is important to evaluate potential harms as well as benefits. 

Randomized controlled trial (RCT), meta-analysis Also: prospective study, cohort study, case-control study, case series


Questions root out the probable cause of a patient's disease or the likelihood that she or she will develop an illness. 

Cohort study
Also: case-control study, case series


Questions concerning patients' experiences.

Qualitative study

Quality Improvement

Questions collect data for the purpose of achieving improvements  in specific healthcare settings.

Randomized controlled trial (RCT) 
Also: qualitative study 

The table above is adapted from:

Ackley, B. J., Swan, B. A., Ladwig, G., & Tucker, S. (2008). Evidence-based nursing care guidelines: Medical-surgical interventions. (p. 7)St. Louis, MO: Mosby Elsevier.

Fineout‐Overholt, E., & Johnston, L. (2005). Teaching EBP: Asking searchable, answerable clinical questions. Worldviews on Evidence‐Based Nursing, 2(3), 157-160.

Finding Evidence Based Resources