WHAT'S GOING TO HAPPEN TO ME DOCTOR? Flashcards
whats a prognosis?
an assessment of the future course and outcome of a patient’s disease, based on knowledge of the course of disease in other patients together with the general health, age, and sex of the patient
what is a prognosis important?
it can help diagnostic and treatment decisions
what are some prognostic factors?
demographic
disease type
if a person have other conditions (co-morbidity)
what are risk factors?
patient characteristics associated with the development of the disease in the first place.
outline a cohort study?
No randomisation of patients into groups
Observation of outcomes over a period of time
Can be prospective or retrospective
Used to identify risk factors for development of a disease as well as prognosis
what’s selection bias?
the distortion is a result of systematic differences in who is selected to be included
whats information bias?
systematic differences in how information is collected
what’s confounding bias?
A systematic distortion in the measure of association between exposure and the health outcome caused by mixing the effect of the exposure of primary interest with extraneous risk factors.
what are advantages of cohort studies?
Measurement of exposure to risk factor(s) not biased by the presence or absence of outcome
Can provide data on time course of development of an outcome
More than one outcome can be examined at once
Useful for investigating rare exposures
what are disadvantages of cohort studies?
Potential for bias due to selection of subjects
Danger of losses to follow-up
Historical studies are dependent on accuracy of records/family/patient recall
Exposure to risk factors/existence of prognostic factors may change over course of study
Can be timely and costly to carry out
outline case-control studies?
‘Cases’ of the outcome of interest are compared to ‘controls’ to identify what factors contribute to the outcome
Retrospective- starts with cases and controls with/without the disease outcome and then looks back to compare risk factors.
what is recall bias?
problems with accurate recall of information if reliant on patient/family accounts.
what are advantages of case-control studies?
Relatively quick to carry out (quicker than cohort)
Can be used to examine outcomes that are relatively rare
what are disadvantages of case-control studies?
Problems with possible bias in selection of cases and controls
Potential for recall bias
Measurement of exposure to risk factors may be biased by presence or absence of the outcome
