WEEK 2: Critical Appraisal Flashcards
What is Critical Appraisal?
Critical appraisal is the systematic evaluation of clinical research papers in order to establish trustworthiness.
Help you appraise the reliability, importance and applicability of clinical evidence.
It is the process of carefully and systematically examining research evidence to assess its validity, results and relevance before using it to inform decision.
An essential skill for evidence-based medicine as it allows clinicians to find and use research evidence reliably and efficiently.
What is the purpose of critical appraisal?
All systematic reviews incorporate a process of critique or appraisal of the research evidence.
The purpose of this appraisal is to assess the methodological quality of a study and to determine the extent to which a study has addressed the possibility of bias in its design, conduct and analysis.
Not all research is of good quality.
There are some studies that are biased and their results untrue.
-Such studies can lead us to draw false conclusions.
What is the Relevance of critical appraisal?
Critical appraisal helps practitioners to decide whether or not a reported piece of research is good enough to be used in decision making.
State the 3 components assessed by critical appraisal.
-Relevance
*Study conducted in similar setting
*Intervention
*Cost, Skill, Patient compliance
*Treatment benefit worth the harm and/or cost
-Validity
*Study assessing clear study question
*Use of appropriate study design
*Randomization
*Minimize drop out
*Blinding
-Results
*Did the finding answer the research question?
*Significance (p-value) and precision (95% *Confidence Interval) of result
*Clinical significance of the finding
*How large was the treatment effect (Absolute risk reduction)
Outline points to consider when evaluating clinical significance.
Was the outcome meaningful to patients or clinicians?
Was the intervention practical?
What were the risks?
What were the costs?
Remember - statistical significance does not equal clinical significance!
State Points to see in searching for evidence.
Decide whether studies have been undertaken in a way that makes their findings reliable
Make sense of the results
Know what these results mean in the context of the decision they are making.
What is Evidence-Based Medicine (EBM)?
It is the process of systematically reviewing, appraising and using clinical research findings to aid the delivery of optimum clinical care to patients.
Defined by Sackett as the “Conscientious, explicit and judicious use of current best evidence in making decisions about the care of individual patients.”
Evidence-based medicine (EBM) has been hailed as a new “paradigm.”
State the 6 Components of EBM.
- Define the problem
- Ask the clinical question
- Find the “best available” evidence
- Critically appraise the evidence
- Apply the evidence to your patient
- Evaluate the outcome of your intervention
Critical appraisal is an essential part of practicing EBM!
State the components of critical appraisal.
A. Study design
B. Sample characteristics
C. Statistical significance
D. Patient outcomes
E. Clinical significance
What is the use of clinically effective interventions in practice is based on?
Appraisal of relevant information or data
Dissemination to relevant staff
Adaption of procedures to meet local needs
Implementation of the evidence through developing guidelines
Define the following types of clinical trials.
1. Therapeutic trials:
2. Preventive trials:
Therapeutic trials: determine the ability of an intervention to reduce symptoms, prevent recurrence, decrease risk of death e.g., can H pylori eradication regimes relieve symptoms in infected patients with non-ulcer dyspepsia.
Preventive trials: can an agent or procedure reduce the risk of developing disease among those free of the condition at enrolment eg mass eradication of H pylori in general population reduce the incidence of gastric cancer
Briefly describe the following:
1. Case-control studies
2. COHORT
3. Randomized control trials
- Case-Control Studies:
Purpose: To investigate the association between a particular outcome or disease (cases) and potential risk factors or exposures (controls).
Design: Participants with the outcome (cases) are compared to those without the outcome (controls), and the presence or absence of specific exposures or risk factors is examined.
Timing: Retrospective; researchers identify
individuals with the outcome and look back to assess their exposure history.
- Cohort Studies:
Purpose: To observe and compare groups of individuals (cohorts) over time to assess the development of outcomes and identify potential risk factors.
Design: Participants are categorized into groups based on their exposure status, and they are followed prospectively to observe the occurrence of outcomes.
Timing: Prospective; researchers follow participants over an extended period, collecting data on exposures and outcomes as they occur.
- Randomized Controlled Trials (RCTs):
Purpose: To evaluate the effectiveness of interventions or treatments by randomly assigning participants to different groups, allowing for the assessment of causality.
Design: Participants are randomly allocated to either the experimental group (receives the intervention) or the control group (receives a placebo or standard treatment). Outcomes are then compared between the groups.
Timing: Prospective; participants are followed over time to measure the impact of the intervention on the outcomes of interest.
