Epidemiology Flashcards
What is epidemiology
Research that would look at the the more detailed questions
This would be on a whole population and not just an individual
What is incidence
The amount of new people that would have been diagnosed with a disease
What is prevalence
The amount of people who would have been diagnosed with the disease and are living with the disease
What is a case study
Investigation in an individual or a group
What is a case series
A study that would be looking at a group of people who would have the same disease
What is an ecological case study
Would look at the association between an exposure and a disease
What is a cross sectional study
Would look at the prevalence
Provides a snapshot of the population at a specific time
This would not been good if a disease would have a short duration
What is a randomised control study and what are its features
The factors of allocation would be random
Random sampling
Single blind or a Double blind study
Crossover or matching can also be used
What is crossover and matching in a RCT
Crossover: group given one medication and then would have it switched later on
Matching: matching patients in the trail based on there certain characteristics
What is a case control study
START WITH THE DISEASE
Look backwards and would see if there would be any exposure and then if you can associate this with the disease
What are the issues with the case control study’s
Involves retrospective so could lead to recall bias
Hard to establish the time of exposure in relation to the disease
Can’t determine causality
What is a cohort study
HAVE THE EXPOSURE AND LOOK TO SEE IF CAUSES THE DISEASE
Need to follow up the patients over a long period of time
Have prospective and retrospective
What is a prospective cohort study
Look forward intime
Cohort - exposure- disease
What is a retrospective cohort study
Look back in time
Look for the exposure (start with this)
Look back to see if they had previously been diagnosed with the disease (look at the history)
What is in the Bradford hill criteria for the causality
Plausible
Consistency
Temporal relationship
Strength
Specificity
Change in the risk factor
What is meant by plausiblilty
Do the factors agree with what is already known about the disease
What is meant by consistency
Are the results consistent with other groups who have done this study
What is meant by a temporal relationship
Did the risk factor appear before the disease developed
If not this may not show cause
What is meant by strength
Do those who have been exposed to the risk develop the disease more frequently then the people who have not been exposed
What is meant by specificity
Is the risk factor mainly only associated with the disease mentioned or would it connect to many diseased
What is meant by change in the risk factor for the criteria
Does the incidence fall or rise when there would be changes in the risk factor
What are the types of selection bias
Sampling bias - not representative
Responder bias - only a certain type of people may respond, those who would have time on their hands or those who want a change to be made
What are the types of information bias
Follow-up bias - not all people would come to the follow up appointments, this would then mean that some information would be missing
Recording bias - more complete data for some then others
Recall bias - respondents can’t remember details
Social acceptability bias - only answer if they think they won’t be judged or if the factor would be social acceptable (if not would lie)
Interviewer bias - interviewer would right down incorrect information or have their own interpretation
What is a confounding factor
Something other then the risk factor in question that could cause the disease
