Critical numbers

Question 1

Incidence

Answer 1

number of new cases occurring in the pre-defined period divided by the number of people at risk

Question 2

What was you take into account with incidence?

Answer 2

Those with genetic conditions predisposing to disease may be excluded from the case group and
population at risk depending on what is being investigated.

Question 3

Incidence rate

Answer 3

no of new cases in a period at risk in a population

Question 4

Prevalence

Answer 4

no of people who have the disease amongst a population at a specific time

Question 5

Case fatality

Answer 5

no. of people who die from disease in a period/ no. of people with disease

Question 6

Mortality rate

Answer 6

no. of people who die from the disease in period/ no. of people who die in
period

Question 7

Risk= probability of disease.

Answer 7

1=certain to happen, 0=certain not to happen

Relative risk= risk for the treated group/risk of the control group x 100

Question 8

Risk ratio

Answer 8

used to find risk factors of a disease
cohort studies
measure of relative risk

Question 9

RR=1

Answer 9

Exposed risk same and unexposed

Question 10

RR

Answer 10

protective effect of exposure

Question 11

RR>1

Answer 11

exposure is associated with harm

Question 12

Relative risk reduction =

Answer 12

100- relative risk (ie. The difference the new treatment makes to the
condition)

Question 13

odds

Answer 13

probability of event/ probability that event does not occur. (or odds= no. of times the

event occurs/no. of times it does not occur)

Question 14

odd ratio

Answer 14

odds for disease of exposed group/ odds of disease of unexposed group

Can be used when a randomised controlled trial is dichotomous

Question 15

Relative risk reduction

Answer 15

means the reduction in risk in the treated group compared to the untreated group

Question 16

Categorical variables

Answer 16

Can only be assigned to a number of distinct categories. subdivided into ordinal and nominal

Question 17

ordinal

Answer 17

categorical variables which can be ordered

Question 18

Bar charts

Answer 18

for categorical or discrete data

Question 19

Pie charts

Answer 19

categorical or discrete numerical

Question 20

Histograms

Answer 20

frequency distribution of continuous variables

area of bar = frequency

Question 21

Normally distributed?

Answer 21

uses mean and standard deviation

Question 22

Non-normally distributed?

Answer 22

median and IQR

So it doesn’t effect the outliers

Question 23

Appropriate test for

Numerical vs numerical?

Answer 23

correlatiom

Question 24

Numerical vs categorical independent groups

Answer 24

t-test

Mann-Whitey test

Question 25

Numerical vs categorical non independent groups

Answer 25

Paired t-test

Sign test

Question 26

Why do larger studies have smaller CI?

Answer 26

larger data groups reduce spread and increase accuracy

Question 27

Standard error

Answer 27

measure of precision
used in calculation of CI
= standard deviation/root of the sample size

Question 28

positive predictive value

Answer 28

probability that someone has the condition if they test positive=number who have disease/no test positive

Question 29

Negative predictive value

Answer 29

Probability someone doesn’t have the condition if they test negative-number who don’t have the disease/number who test negative

Question 30

Validity

Answer 30

measures accurately what is meant to be measured

Question 31

Responsiveness

Answer 31

can detect real changes when they occur

Question 32

Inductive hypothesis?

Answer 32

proposed after analysis

Question 33

Deductive hypothesis?

Answer 33

proposed before analysis

Question 34

Referencing an article?

Answer 34

JOURNAL ARTICLE (print): family name INS. Title of article. Journal. Year (and date) ; vol(issue) : pages