Epidemiology and ethics Flashcards
equation for odds ratio? equation for relative risk?
OR - (A/B)/(C/D)
RR - (A/A+B)/(C/C+D)
when is the odds ratio a good approximation of relative risk?
low prevalance
What does it mean when relative risk is equal to one?
no relationship between exposure and diagnosis
what is most important in a screening test? what is most important in confirmatory test?
increased sensitivity
increased specificity
equation for sensitivity
A/A+C
equation for specificity
B/B+D
equation for PPV
A/A+B
equation for NPV
D/C+D
bias where memory errors produce incorrect data
recall bias
bias where subject awareness of being studied alters their answers and behavior from normal
observational bias
bias where certain medical studies attract subjects with particular medical histories rather than general population
self selection bias
bias where studies that show a difference are preferably published and then later included in meta analysis rather than studies that support null hypothesis
publication bias
bias where screening tests designed to detect asymptomatic disease may miss rapidly progressive disease because the interval between successive screenings only detects slowly progressive ones
length bias
bias where screening test may allow earlier diagnosis of disease but does not translate into actual length of survival
lead time bias
What should you do in the case of a child’s parents refusing a clearly life saving treatment for their child in an emergency situation?
Emergency - give life saving tx, get court order later
Non emergency - get court order
Ca patient is emergently intubated in the ER after a motor vehicle accident. The patient’s family brings you a DNR signed by the patient stating that she does not wish to be intubated. What do you do?
extubate
Where in the US is euthanasia legal?
nowhere
patient has a living will that sates he does not want to be placed on a ventilator. His wife tells you to place him on the ventilator for one week and then remove it if he is not improving. What should you do in this scenario?
follow living will
what ethical problem exists when a doctor refers a patient for an MRI at a facility he owns
conflict of interest
Does a cohort study identify incidence or prevalence?
incidence and prevalence
What biostatistical calculation looks at individuals with and without a disease and determines the likelihood of exposure to a risk factor
odds ratio
