Study Types - Pros And Cons

Question 1

Power definition

Answer 1

Probability of picking up a significant difference if there is one (1-type II error)

Question 2

p value

Answer 2

Probability event occurs by chance (ie getting type I error)

Question 3

Type I error

Answer 3

Wrongful rejection of null hypothesis eg false positive

Question 4

Type II error

Answer 4

Wrongful acceptance of null hypothesis eg false negative

Question 5

Confidence interval

Answer 5

Estimate or range in which the true value will lie

Question 6

NNT

Answer 6

1/ (incidence in control - incidence in exposed)

Question 7

Pros and cons of surrogate endpoints

Answer 7

Enable earlier evaluation of intervention -> cheaper + shorter study duration +/- size

Cons: if not very good predictor of clinical outcome then can lead to false interpretations of intervention efficacy

Question 8

Pros and cons of composite outcomes

Answer 8

Can help increase power of study when outcomes are rare/when events are competitive

Con: If effect is produced then you can’t assume its for all components of composite outcome

Question 9

Reporting for systematic reviews and meta-analysis

Answer 9

PRISMA (preferred reporting for systematic reviews and meta-analyses)

Question 10

Reporting for RCTs

Answer 10

CONSORT (consolidated standards of reporting trials)

Question 11

Reporting for cohort/case control

Answer 11

STROBE (The strengthening and reporting of observational studies in epidemiology)

Question 12

Reporting for case reports

Answer 12

CARE (Consensus based clinical reporting)

Question 13

Biases reduced by blinding

Answer 13

Interventional

Expectation

Question 14

Biased reduced by intention to treat analysis

Answer 14

Attrition bias