Transcript What did statistics ever do for you?

Statistics for Health Research
What has Statistics
ever done for you?
Peter T. Donnan
Professor of Epidemiology and Biostatistics
Contemplating
statistical
analysis
Contemplating
statistical analysis
The power of collecting and
analysing data
“…..those who fell before
Sebastopol were seven times
the number who fell by the
enemy”
Mortality Statistics collected
by Florence Nightingale, which
led to a public outcry
What did statistics ever do
for you?
• Uncovered unknown
associations and likely
causality: Smoking and
lung cancer
•Efficacy of drug
treatment: statins on
cholesterol and
mortality (WOSCOPS)
What did statistics ever do for
you? Clinical Decision Aids
• Prediction of
risk:
Cardiovascular
(Framingham)
55 yr-old
woman
15-20%
5yr risk
What did statistics ever do
for you?
• Statistical analysis usually required for
demonstration of efficacy of medication
Discovery
of Insulin
December 15th, 1922
February 15th, 1923
What statistics cannot do for
you!
• ‘Fix’ results to give answer
wanted
• Adjust for poor design:
biased sampling,
sample too small,
no comparators
The ubiquity of numbers
…….all that scientists are looking
for is a quick fix without the
encumbrance of a meaningful
relationship (with statistics)
Stephen Senn, 2003
The ubiquity of numbers
Most aspects of reality
amenable to measurement or
categorisation
Quantitative methods provide
powerful set of tools for
summarising and drawing valid
conclusions
Statistics as a tool to
model reality
All models are wrong, but
some models are useful
George Box
Detecting signal from
background random noise
To Sum up
Statistics is about • Design
• Decision in the face of
uncertainty
• Evaluating evidence
• Dealing with chance
It is all-pervading in science but frequently
misunderstood
If you think statistics has nothing to do
with you then you are wrong!
Objectives of Statistics
Course
• Understand nature of data
• Understand fundamental concepts in
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•
•
•
statistics
Read data into SPSS
Produce summary and descriptive
statistics in SPSS
Carry out simple tests using SPSS
Carry out regression in SPSS
Experienced Statisticians in
Health Research
• Simon Ogston
• Adrian Hapca
• Nicosha De Souza
• Thenmalar Vadiveloo
• Huan Wang
• Simone Hapca
• Petra Rauchhaus
Statistics Course
• Assume little knowledge of
statistics
• Start with summarising and
presenting data
• Move on to drawing inference
from numerical information and
modelling
Finally
• http://my.dundee.ac.uk
• Username: pgstatstudent
• Password: pgstat
Contemplating
statistical analysis