Sampling Techniques Flashcards
What is random sampling?
All members of the target population have an equal chance of being selected
Strength of random sampling?(bias)
Researcher has no control over who is selected - investigator bias avoided
What is a limitation of random sampling?(representative)
There is still a chance results may not be representative therefore limiting generalisability
What is systematic sampling?
Mathematical selection of participants when the population size is divided by sample size
What is a strength of systematic sampling?(bias)
The only input the researcher has is deciding the sample size so investigator bias is avoided
Limitation of systematic sampling?(representative)
Same as random sampling - may not be generalisable
What is stratified sampling?
Aims to ensure that the key characteristics of the population are represented in the same proportion in the sample
Strength of stratified sampling?(bias/representative)
As all key characteristics are represented, it avoids investigator bias and it also representative
Limitation of stratified sampling?(key features)
If perhaps all key features aren’t shown then it may lack generalisability
What is opportunity sampling?
Sample that consists of participants who were selected due to their availability
Strength of opportunity sampling?(time)
Selection is straightforward therefore less time consuming
Limitation of opportunity sampling?(bias)
Aware/unaware, the researcher may show bias, limiting generalisability
What is volunteer sampling?
Participants self-select
Strength of volunteer sampling?(time)
Selection is straight forward therefore less time consuming
Limitation of volunteer sampling?(bias)
Sample bias is likely as only certain types of people are motivated to volunteer - limiting generalisability
