5.1 review

Question 1

difference between representative and random?

Answer 1

random = not intended to be representative of population.

representative = take a sample from a population to represent the larger population

Question 2

difference between incidence and prevalence?

Answer 2

incidence = new cases in a time dimension e.g cases per year

prevalence = both old and new cases. no units

Question 3

what is a ratio of benefit and ratio of harm?

Answer 3

ratio of benefit = 1/ratio of harm

ratio of harm = 1/ratio of benefit

Question 4

what is a 95% confidence interval?

Answer 4

the range within which we can be 95% certain that the true value of underlying tendency really lies

Question 5

what is the p value?

Answer 5

the probability of getting an observation as extreme as, or more extreme than the one observed assuming that the stated hypothesis is true

Question 6

what is the difference between as treated and intention to treat?

Answer 6

as treated = patients have actually received treatment and are studied

intention to treat = randomised regardless of compliance and are studied

Question 7

what is the use of a forest plot?

Answer 7

a graphical representation of the meta analysis

lines on either side of square show the confidence interval for that study

Question 8

what is the use of a funnel plot?

Answer 8

used to check the existence of publication bias in systemic reviews

Question 9

what is statistical significance?

Answer 9

if P value is less than or greater than 0.05

if P value of a new intervention to a comparison is less than 0.05 then the intervention is more effective than the comparison

Question 10

what is the com-b model?

Answer 10

Capability
motivation
opportunity

will all lead to a change in behaviour for health improvement