Level 2
Level 4

#### 28 words 0 ignored

Ready to learn
Ready to review

## Ignore words

Check the boxes below to ignore/unignore words, then click save at the bottom. Ignored words will never appear in any learning session.

**Ignore?**

Nominal Variables

Assigned to a category with no natural ordering e.g. hair colour

Ordinal Variables

Categories which are ordered e.g. level of satisfaction

Discrete Variables

only takes whole numerical values e.g. number of people

Continuous Variables

Variables have no limitation on values e.g. weight

Histograms

visually display frequency distribution of continuous variables

Standard Deviation

a quantity expressing by how much the members of a group differ from the mean value for the group

Epidemiological triad

the time place and person

Incidence

the number of new cases in a period/population

Prevalence

how many people have a disease amongst a population at a specific point in time

Person-time

way of determining how many people at risk

Case fatality rate

number of people who die from the disease in a period/number of people with disease in period

Mortality rate

number of people who die from disease in period/number of people who die in period

Types of Studies

Check my I+P Memrise

Risk

number of new cases/number at risk

Odds of an event

probability of event/probability that event does not occur

Odds ratio

the measure that is calculated to represent the relative risk for a case-control study

Relative Risk

used with Cohort studies only

RR = 1

no benefit or harm

RR less than 1

exposure is protective

RR more than 1

exposure is harmful

Mean

summarise a normally distributed variable

Median

summarise an abnormally distributed variable

IQ range

used with median, measure of spread

Confidence intervals

measure accuracy

T test

determine whether the means of two different groups are statistically significant from one another

P value

the probability of obtaining the results given that the null hypothesis is true

Correlation less than 0.7

treat with suspicion

Chi squared test

goodness of fit