Clinical Epidemiology Flashcards
epidemiology
science of distribution and causes of disease in populations
clinical epidemiology
science making predictions about patients using tools of epidemiology
sensitivity
the extent to which the test is accurate for those who have the disease in question, avoiding false negatives
specificity
the extent to which the test is accurate for those who do not have the disease, avoiding false positives
positive predictive value
the extent to which a positive test indicates the presence of disease
negative predictive value
the extent to which a negative test indicates the absence of disease
Receiver Operator Characteristics (ROC)
y-axis (sensitivity- true positives) and x-axis (specificities- false positives)
Where is the most accurate test overall located on the ROC (reciever oerater characteristic) graph and why?
upper left corner becuse test is most specific and sensitive
Label each letter and number
A. Positive for the disease
B. Negative for the disease
C. Positive test
D. Negative test
- Sensibilty; True positives
- False positives
- False negatives
- Specificity; True negatives
prevalence
the probability of having a disease at a given point in time also known as pre-test probability
cumulative incidence
new cases of disease in the population at risk of getting the disease over a period of time; (number of new cases of disease over a period of time)/(number of people at risk of getting disease)
prevelance equation
incidence x average duration
attack rate, mortality rate, and case fatailty rates
types of cummulative incidence
results of a test can/cannot be interpreted correctly without knowing the pre-test probability
cannot
four factors that determine how thresholds are set
- accuracy of test
- risk of test
- seriousness of the illness and the benefit of treatment
- risk of treatment
