EBM Flashcards
Give the criticism of EBM
Academic exercise, not relevant to practice
Not appropriate for GP
No time to critically appraise articles
Bad decisions by governments and healthcare commissioners have been made based on EBM
What is the hierarchy
Systematic review and meta analysis Randomised control trials Cohort studies Case-control studies Ecological studies Descriptive/cross-sectional studies case report/series
What can EBM be used to find
clinical findings Aetiology Clinical manifestation of disease Diagnostic tests Prognosis
Define association
Statistical dependence between 2 variables
How can the role of chance be assessed
Statistical significance tests and confidence intervals
Define confidence intervals
The range within which the true value is expected to lie with a given degree of certainty
Define bias
A systematic error leading to an incorrect estimate of the effect of an exposure on the development of a disease or outcome or interest
How is bias controlled in analysis
Cannot be controlled in analysis and cannot be eliminated by increasing the sample size
What are the two broad types of bias
Selection and measurement
Describe selection bias
Occurs when there is a systematic difference between characteristics of the people selected and those who were not
Healthy entrance effect
Loss to follow up
Non-response bias
Describe measurement bias
When measurements of classifications of disease or exposure are inaccurate
Recall bias
What is a confounder
any factor which is believed to have a real effect on the risk of disease under investigation and is also related to the risk factor
What are some common confounders
Age, sex, socio-economic status, geography
How can bias be dealt with at the design
Randomisation and restriction/matching
How can bias be dealt with during analysis
Stratification, standardisation or regression
