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Question 1

what is a prob;em in case control studies

Answer 1

recall bias

Question 2

Occurs when two tests for a disease are compared, the new test diagnoses the disease earlier, but there is no effect on the outcome of the disease

Answer 2

lead time bias

Question 3

describes a group changing it’s behaviour due to the knowledge that it is being studied

Answer 3

hawthorne effect

Question 4

clinical trial phase 1,2,3

Answer 4

1= safety
2= efficacy
3= effectiveness

Question 5

variables within a study leadinf to spurious results

Answer 5

confounding

Question 6

Once correlation between two variables has been shown —- can be used to predict values of other dependent variables from independent variables.

Answer 6

regression

Question 7

intention to treat trial includes pts who

Answer 7

dropped out the trial

Question 8

is a measure that indicates how many patients would require an intervention to reduce the expected number of outcomes by one.

Answer 8

number needed to treat

Question 9

what checks for publication bias

Answer 9

funnel plot

Question 10

If the risk ratio is > 1 then the rate of an event (in this case experiencing significant pain relief) is increased compared to controls.

Answer 10

The precision quantifies a tests ability to produce the same measurements with repeated tests.

Question 11

Proportion of patients without the condition who have a negative test result

Answer 11

specificity

Question 12

sensititivty Proportion of patients with the condition who have a positive test result

Answer 12

positive predictvive value-Proportion of patients with the condition who have a positive test result

Question 13

A null hypothesis (H0) states that two treatments are equally effective

Answer 13

power is the probability of detecting a stastisitcxally significant difference

Question 14

snapshot - prevalence study
casre control - find pts who have condition
cohort - gorups followed