W7 Evidence based medicine Flashcards
What is the definition of Evidence-Based Medicine?
Evidence based medicine is the * use of current best evidence in making decisions about the care of individual patients.
*(conscientious, explicit, and judicious)
Why do we need evidence-based medicines?
- To ensure medicines sold are of high quality, safety and efficacy
*They are the basis for the recommendations we make to patients and other health professionals through pharmacy services - It is essential that pharmacists are available to retrieve, appraise and apply research evidence as the basis for clinical decision making
What is an example of observational study?
What is an example of experimental study?
-Cross-sectional study/ Cohort study/ Case-control study
-Animal testing/ RCTs
What are the two types of Experimental Study design? (2)
Basically uses experiments
1. Animal and laboratory studies. Involves animals e.g. guinea pig, rat. Prior to human trials.
- Randomised controlled trial (RCT) – Involves humans (and considered the Gold standard)
Animal and laboratory study:
What is tested?
What are the Disadvantages?
*Animal research uses animals to test potential pharmaceuticals prior to human trials
* Its application is limited considering the difference between human and animal physiology, not ethical
* Experiments are undertaken in a highly controlled environment
What is case-control study?
-Retrospective in nature
- Well-designed
- Cases have outcome of interest whereas control lacks the outcome of interest
- Determines which factors contribute to an outcome
e.g. Why some patients need longer intensive therapy than others for tuberculosis
What are the pros and cons of case-control study design
Advantages:
* Less expensive
* Easier to do and take less time
* Useful when obtaining follow-up data that is difficult to obtain due to the nature of population being studied
* More efficient if the disease is rare
* This design may be the only ethical way to evaluate
something
Disadvantages:
* Potential recall bias
* Subject to selection bias
* Generally do not allow investigators to calculate an incidence or absolute risk
What are Cross-sectional studies?
- An observational study design where outcomes and exposures are measured concurrently (at the same time)
- Participants are selected based on set inclusion and exclusion criteria.
*Mainly used in Population based research - There is a target population and a small study sample is taken from this
e.g. Testing if there is correlation between smoking and COPD, both are tested at same time
Exposed and outcome present = Has both
Exposed and no outcome = Smokes but no COPD
Unexposed and outcome= X smoke has COPD etc
What is a Randomised Controlled Trial (RCT)?
-Prospective study*
- Randomly assigned subject to receive control (treatment/placebo)/intervention
*A research study that follows over time groups of individuals who are alike in many ways but differ by a certain characteristic
What are the Advantages and Disadvantage of Randomized Controlled Trials (RCT) ?
Advantages
* Considered the gold standard
* This design allows for washout of most population bias
* Reduced influence by confounders
* Reduced variability in the outcome(s)
* Easier to blind patients than observational studies
Disadvantages
* More time consuming
* More expensive
What is a Systematic Review?
- Identify relevant research studies (A literature review) done by researchers
-To locate, appraise and synthesise the best available evidence(relating to a specific research question)
- To provide informative and evidence-based answers.
- Combine with professional judgment to make decisions about how to deliver interventions or to make changes to policy.
Highest level of evidence, secondary evidence
Follows rigorous protocol
Collects all known research
Systematic review Vs Meta Analysis:
Systematic- Only to identify relevant research
Meta- Gather information from research then carry out a statistical test
What is a Meta-Analysis?
What is the adv and disadv?
The use of statistical methods to summarise the results of independent studies. By combining information from all relevant studies, meta-analysis can provide more precise estimates of the effects of health care than those derived from the individual studies included within a review.
Advantage
* Objective evaluation of research findings
Disadvantage
* Not all topics have sufficient research evidence to allow a meta-analysis to be conducted
What are some advantages of Guidelines (e.g., NICE guidelines)
- Are on topic of relevance to population (usually determined by NHS England or the Department of Health and Social Care).
- Thorough and transparent development process to ensure fairness.
- Representative stakeholders involved in the process.
- Guidelines are developed using thorough literature reviews of many RCTs and other forms of evidence.
- Directly applicable to patients.
- Often take into account a huge number of potential treatments and drug classes, e.g. type 2 diabetes guidelines.
- Complex issues simplified.
- Regularly reviewed.
- Take into account cost considerations.
What are the Disadv of Guidelines (e.g., NICE guidelines)?
- Many resources so a lot of literature review to do
- Conflict of interest sometimes
