Critical numbers

Question 1

incidence

Answer 1

number of new cases that develop in a given period of time

Question 2

prevelence

Answer 2

number of cases of a disease that are present in a particular population at a given time

Question 3

absolute risk

Answer 3

change in the risk of an outcome of a given treatment or activity in relation to a comparison treatment or activity

Question 4

relative risk

Answer 4

ratio of the probability of an event occurring (for example, developing a disease, being injured) in an exposed group to the probability of the event occurring in a comparison, non-exposed group

Question 5

odds ratio

Answer 5

the odds that an outcome will occur given a particular exposure, compared to the odds of the outcome occurring in the absence of that exposure

Question 6

sensitivity

Answer 6

probability of a positive test among patients with disease

Question 7

specificity

Answer 7

probability of a negative test among patients without disease