Wk 2- Biomed Skills: Scientific Method and Experimental Design

Question 1

Scientific method

Answer 1

The acceptable, logical path used to gain evidence that answers Qs about observable phenomena

Question 2

Mnemonic for steps in scientific method

Answer 2

Only hippos eat dirty coke cans

Question 3

Steps of scientific method

Answer 3

Observe
Hypothesis
Design and perform exp
Collect, analyse, interpret data
Conclusion
Communicate findings

Question 4

Observe

Answer 4

Observe phenomena and research
ID gaps in knowledge

Question 5

Hypothesis

Answer 5

What causes the phenomenon?
Aims: What Q do you want to answer?

Question 6

Design and perform exp

Answer 6

Protocol and procedure
ID type of data

Question 7

Collect, analyse, interpret data

Answer 7

What data
How is it collected
How is it analysed

Question 8

Conclusion

Answer 8

Does the data support your hypothesis?
Yes- Repeat 3* for reliability
No- Repeat and make sure, adjust hypothesis if necessary

Question 9

How are ideas generated

Answer 9

Reading literature and observing analogies b/n systems or patterns / breaks in patterns
New tech thus new Qs
Intuition, imagination, observation
Talking to clinicians and patients

Question 10

How was Penicillin discovered?

Answer 10

1928
Alexander Fleming found that staph on culture plate were killed by Penicillium notatum
Grew culture and produced penicillium

Question 11

What is outside scientific investigation?

Answer 11

Phenomena that cant be repeated or measured
Phenomena that cant be tested

Question 12

Homeopathy

Answer 12

Alt medicine
Diliution of disease causing agent in the theory that water holds the ‘memory’ of it
Proven to be false
6757 papers on Pubmed as of March 2024
e.g. Paper showing activation of basophils using dilute IgE antiserum shown to be false

Question 13

What should be considered when planning and designing an exp.?

Answer 13

Type of study
Control vars
Min bias
Analysis of results
Presentation of results
Logistics

Question 14

Types of studies

Answer 14

Observational
- Descriptive (single case/group)
- Analytical (comparison b/n groups)
Experimental ( control vars)
Longitudinal (group over time)
Prospective (present/future)
Retrospective (past)
Cross-sectional (Single point in time)

Question 15

Types of variables

Answer 15

Independent (X)
Dependent (Y)
Nuisance
Confounding

Question 16

Relationship b/n X and Y

Answer 16

X causes Y

Question 17

Nuisance vars

Answer 17

Change Y outside of X
Must be controlled

Question 18

Examples of nuisance vars

Answer 18

Bio var
Envir.
Time
Sampling bias
Researcher bias
Participant bias
Social and cultural context

Question 19

Confounding vars

Answer 19

Change at the same time as X
e.g.
X= Alzheimer’s
y= Memory loss
Confounding var= Age

Question 20

How are confounding vars controlled?

Answer 20

Case control design- Study group compared to like controls

Question 21

+ controls

Answer 21

Ensure result obtained is actually +

Question 22

• controls

Answer 22

Ensure no false +

Question 23

Example of a control

Answer 23

DNA of mice labelled w/ brdU
Mice performed dif tasks
Control group allowed stat analysis to be performed on exercise groups
Increased brdU indicated neurogenesis

Question 24

How can vars be controlled?

Answer 24

Randomisation
Double-blind placebo-control trials (remove patient and clinician bias). Code unlocked at end
Controlled exp conditions recorded in lab journal
Sample size

Question 25

Why is it important to record exp conditions?

Answer 25

So that it can be repeated by others to ensure validity
One exp only valid for one time, place, operator, subject, technique