Experiments, surveys, sampling, estimation, cohort studies, meta-studies and computer modelling
List as many methods as you can.
| Method | Example use | Advantage | Disadvantage |
|---|---|---|---|
| Experiment | Testing enzyme activity | Variables can be controlled | May be artificial or time consuming |
| Survey | Health behaviour questionnaire | Can collect lots of responses | Answers may be biased or inaccurate |
| Sampling | Estimating species in a field | Faster than measuring everything | Must be representative |
| Cohort study | Following people to study disease risk | Shows long-term patterns | Expensive and slow |
| Meta-study | Combining published drug trials | Can increase confidence | Depends on quality of original studies |
| Computer model | Climate or disease spread prediction | Useful when real experiments are impossible | Depends on assumptions and data quality |
Scientists change or compare one variable and measure the effect on another variable.
Example: testing how temperature affects enzyme activity.
Scientists collect answers from people using questionnaires or interviews.
Example: asking patients about symptoms, lifestyle or treatment side effects.
Sample locations or participants are chosen using chance, such as random coordinates.
Samples are taken at regular intervals, such as every 5 m along a transect.
Estimation uses sample data to predict a larger total when counting everything is impractical.
Example: estimating the number of daisies in a field by counting daisies in several quadrats.
A lake has thousands of tiny aquatic organisms spread throughout it.
A cohort study follows a group of people over time to look for links between risk factors and outcomes.
Record baseline data
Collect health data
Look for risk factors
Identify patterns
A meta-study or meta-analysis combines results from multiple studies to look for an overall pattern.
Computer models simulate complex systems that may be too large, slow, dangerous or impossible to investigate directly.
Examples: climate change, disease spread, drug design, space flight and weather prediction.
Press start to begin.
Scientific data should be collected from a sample that represents the people or population the conclusions will be applied to.
| Example | Method? |
|---|---|
| Combining results from 30 published trials of a medicine | ? |
| Asking 2,000 people about their exercise habits | ? |
| Taking quadrat samples every 5 m along a transect | ? |
| Following a group of people for 20 years | ? |
| Predicting how a disease may spread through a population | ? |
Press start to begin.
Click each keyword and add the model definition to your notes.
Answer these in full sentences:
A student wants to estimate the number of bluebells in a large woodland. The woodland is too large to count every plant.
| Quadrat | Bluebells counted |
|---|---|
| 1 | 12 |
| 2 | 18 |
| 3 | 9 |
| 4 | 15 |
| 5 | 11 |
Task: Explain whether sampling and estimation are appropriate.
Scientists want to investigate whether smoking is linked with cardiovascular disease. They cannot ethically ask people to start smoking.
| Group | Data collected over time |
|---|---|
| Smokers | Blood pressure, cholesterol, diagnosis records |
| Non-smokers | Blood pressure, cholesterol, diagnosis records |
Task: Choose a suitable method and justify it.
Answer each question. Your score will appear at the end.