Lecture 1: Intro

Question 1

What is biostatistics?

Answer 1

Biostatistics is the application of statistical tools in health sciences

Biostatistics is a growing field with many applications in Medical sciences, Epidemiology, Environmental sciences and educational research.

Question 2

True or false?

Answer 2

True

Question 3

How is biostatistics applied in healthcare?

Answer 3

• Conducting medical research
• Understanding medical/epidemiological problems
• Appraise/interpreting the literature
• Clinical decision making
• Interpreting vital statistics
• Determining health policy
• Implementing diagnostic procedures

Question 4

What is data/observations?

Answer 4

Observations/data are obtained from individuals.

Question 5

What is a population?

Answer 5

A set of all individuals of interest

Question 6

Data types determine?

Answer 6

The choice of analysis

Question 7

What are the two types of data?

Answer 7

Categorical - qualitative

Numerical - quantitative

Question 8

What is categorical (qualitative) data?

Answer 8

Data describing qualities, places, individuals in distinct groups

• Names and labels are used
• Categories are created based on characteristics

Examples:

    Marital status
    Eye color
    Pain severity
    Smoking status

Question 9

What is Numerical (quantitative) data?

Answer 9

Data that can be measured and expressed numerically

• Data are always in the form of counts or measurements
• Data are always numeric

Question 10

Numerical (quantitative)data can be divided in?

Answer 10

Discrete- counts

Continuous - measured

Question 11

What is Duscrete data?

Answer 11

Can only take on certain values

Examples:

Number of kids

Number of heart beats

Question 12

What is continuous data?

Answer 12

Can take on any value in a continuous scale

Examples:

Height
Age
Weight

Question 13

Stevens claimed that all measurements were based on four types of scales

Answer 13

Nominal
Ordinal
Interval
Ratio

Question 14

What are the types of scales?

Answer 14

Nominal scale
Ordinale scale
Interval scale
Ratio scale

Question 15

What is the Nominal scale?

Answer 15

• Classifications of distributions
• No magnitude or order
• Examples: ethnicity ( White-British, Afro Caribbean, Asian etc)

Question 16

What is the Ordinal scale?

Answer 16

• Any scale that is ordered

* Examples: aggression (weak, moderate intensity, strong)

Question 17

What is the Interval scale?

Answer 17

• Any scale of measurement with no absolute zero point, equal intervals
• Example: Temperature

Question 18

What is the Ratio scale?

Answer 18

• Any scale with equal intervals, absolute zero point

* Example: Weight, Height

Question 19

What is the Binary or dichotomous variable?

Answer 19

Answers can take only two possible values
•Do you own a car? “yes” or “no”
•Does a patient have diabetes “yes” or “no”

Question 20

What is the independent vs dependent variable study?

Answer 20

Study set up to measure the effect of one variable on another

Question 21

What is the Independent variable?

Answer 21

Variable we expect to have an I,pact

Sometimes referred to as exposure or explanatory variable

Question 22

What is the Dependent variable?

Answer 22

Affected by the independent variable

Sometimes referred to as the outcome variable

Question 23

The type of data determines

Answer 23

• Descriptive statistics: how the data is summarised

* Inferential statistics: the statistical test used to form conclusions about the data