How Science Works Flashcards
How is a correlation established?
Large amounts of data are needed to ensure statistical significance
List 3 different types of general risk factors
Genetics
Physical environment
Social environment
Lifestyle and behaviour choices
What is a null hypothesis?
The assumption that there is no difference between an experimental group and a control group. The aim is to disprove it.
Why do scientists try to disprove a null hypothesis rather than prove a hypothesis?
Often it takes less energy to disprove something than to prove it; in the scientific community until something is proved impossible, it’s still possible.
What are the features of a good study?
Controlling variables - Increasing validity
Clear Aim
Representative sample
Valid and reliable results
What is a cohort study?
Where a group of people are followed over time to see who develops the diesease
What is a case control study?
Where a group of people who have the disease are compared with a group who don’t have the disease
What is a risk?
The probability of an unwanted event or outcome
What is probability?
The likelihood of something happening. This has a precise mathematical meaning and is always associated with a time period/ condition
Why is the risk of anything never zero?
There is always the chance of something happening given different circumstances.
List 5 different reasons why people will overestimate risk?
When it is: Not under their control Not natural Unfamiliar Dreaded Unfair Very small
Why might a risk be underestimated?
When it has an effect in the long term future
What information do scientists need to draw a good conclusion after the experiment/investigation has taken place?
Indication of sample size
Data analysis
Indication of other variables
What is the importance of using a control?
Comparison
What always needs to be considered when questioning reliability?
Sample size
Time scale (Long or Short term?)
Variables
Error bars
What is often the reason for tiredness?
Lack of energy
What is often the reason for breathlessness?
Lack of oxygen
What must answers about weight always talk about?
Energy (im)balance
Energy input =/> Energy output
What is a possible consequence of a very low fat diet and very active lifestyle
Loss of weight
Reduced metabolic rate
Lack of protein
