Lecture 1 and 2

Question 1

what is statistics?

Answer 1

statistics is the science of learning from data, and of measuring, controlling and communicating uncertainty

Question 2

biostatistics?

Answer 2

Biostatistics is the development and application of statistical methods to answer research questions in the health sciences.

Question 3

Who holds the responsibility for making sense of data?

Answer 3

researcher, journalist and consumer

Question 4

The scientific method

Answer 4

The scientific method is a process we use to gain knowledge and understanding through testing of hypotheses.

Question 5

Statistics provides much of the ….

Answer 5

framework and mechanisms for implementing the scientific method.

Question 6

order of events in the scientific method

Answer 6

start with observation and then form a hypothesis (based on the observation) then make predictions and then design and carry out an experiment/study to test hypothesis (collecting data) and then lastly accept/reject/refine theory (interpret results)

The scientific method aims to get you closer to the scientific truth

Question 7

The importance of reliable evidence

Answer 7

The reliability of the evidence regarding our hypothesis is critically dependent upon the quality of the research.

• Evidence based policy
• Evidence based practice

Question 8

Evidence based policy

Answer 8

Aims to apply the best available evidence gained from the scientific method to policy making.

evidence based notion used in policy e.g. government such as the bowel screening programme

quality of diagnostic test (efficacy) checked before policy changed is an example of this

Question 9

Evidence based practice

Answer 9

Preferential use of interventions or actions for which systematic empirical research has provided reliable evidence of benefit.

în practice means at the individuals level for example in a clinical trial

Question 10

Health sciences research goal

Answer 10

Goal: to improve the health and well-being of individuals and communities

Question 11

Health science research involves

Answer 11

This involves…
prevention of disease
treatment of disease
promotion of health

Question 12

In order to do health science research we need knowledge about…

Answer 12

causes of disease
diagnosis of disease
disease process (natural history)
 effective treatments
societal factors which affect health

Question 13

wrong/inaccurate data =

Answer 13

wrong/misleading conclusion

Question 14

Research is a process for

Answer 14

providing reliable answers to questions for which the answer is not immediately available.

Question 15

Scientific research provides a

Answer 15

systematic process for obtaining reliable answers to such questions

reliable = reproducible research
defining the research questions leads to quantifiable evidence

Question 16

five steps of the research process

Answer 16

1 Development of research question (ends to be well defined)
2 Design of study
3 Collection of data
4 Description/analysis of data
5 Interpretation of results

all of these steps are essential and none can be skipped

Question 17

specification of the research question

Answer 17

The specification of the research question will include determination
of a model for the process under study, and any hypotheses to be tested.

Question 18

what does the study design refer to?

Answer 18

The study design refers to the methods used to select the study participants, control any experimental conditions, and collect the data.

how we collect data, from which group

Question 19

Inference

Answer 19

The aim of most research studies is to use data from a sample to draw inference about a particular characteristic of a larger population.

cycle is underlying population - sample - statistics - inference - underlying population etc

Question 20

How do you get the best guess at true data?

Answer 20

Best guess at the true data is done by using your sample

you do not expect to be as accurate as if you tested whole population

with successive samples estimates would express variability

Question 21

Model

Answer 21

A model describes the relationships between the quantities of interest in a population

Question 22

Variability and uncertainty

Answer 22

There is variability (or natural variation) in almost everything we may wish to measure
This leads to uncertainty about true value of the quantity or relationship we wish to measure.
Statistics provides a framework for answering questions from data in an atmosphere of uncertainty
We describe this uncertainty using the language of probability
A statistical model takes account of the uncertainty, and includes a mathematical description of the way the data are generated.

what ever we are measuring is subject to random variability

Question 23

A statistical model takes …

Answer 23

account of the uncertainty, and includes a mathematical description of the way the data are generated.

describes the relationship between multiple variables of interest

Question 24

bias as an area is easy or difficult to deal with?

Answer 24

it is difficult to deal with this systematic error and it affects the results