How to read a systematic Review and Meta-analysis and apply the results to patien care.

Revisión Sistematica: revisiones focalizadas en preguntas clínicas. Acompñada pero no siempre de un metaanalisis.

Credibilidad y confiabilidad.
The Process of Conducting a Systematic Review and Meta-analysis
1. Formulate the question
2. Define the eligibility criteria for studies to be included in terms of Patient, Intervention, Comparison, Outcome (PICO), and study design
3. Develop a priori hypotheses to explain heterogeneity
4. Conduct search
5. Screen titles and abstracts for inclusion
6. Review full text of possibly eligible studies
7. Assess the risk of bias
8. Abstract data
9. When meta-analysis is performed:
• Generate summary estimates and confidence intervals
• Look for explanations of heterogeneity
• Rate confidence in estimates of effect.

Guide for Appraising and Applying the Results of a Systematic Review and Meta-analysisa

First Judgment: Evaluate the Credibility of the Methods of Systematic Review

• Did the review explicitly address a sensible clinical question?

focus and address questions defined by particular patients, interventions, comparison and outcomes. the eligibility criteria did improve the poblation of study.

• Was the search for relevant studies exhaustive? 

multiple database for search, multiple synonyms for terms are needed.

• Were selection and assessments of studies reproducible?

having 2 o more reviewers participate, elegilibity por quality (statistic)

• Did the review present results that are ready for clinical application?

MA estimates of effect size (the magnitude between groups).

The form of presentation of units of results. 

Results of meta-analyses are usually depicted in a forest. The point estimate of each study is typically represents a square with a size proportional to the wight. and the IC as a horizontal line. The combined result as a diamond.  

More weight and precision 

• Did the review address confidence in estimates of effect?.

RS well conducted credible, the bias and the heterogeneity is explicated,

Second Judgment: Rate the Confidence in the Effect Estimates

What is the confidence in the estimates of effect?

GRADE system for evaluate the quality of evidence. Hig moderate, low and very low. the confidencie can low whith bias, imprecision, inconsistency.

• How serious is the risk of bias in the body of evidence?

the sistematic review should be demostrate the form of calculate the risk of bias and demostrate that is low and confidence.

• Are the results consistent across studies?
• How precise are the results?
• Do the results directly apply to my patient?
• Is there concern about reporting bias?
• Are there reasons to increase the confidence rating?

Why use systematic review and metanalysis: Representative, >confidence.