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Rehab Research
Chapter 9- Selection and Assignment of Participants
Question | Answer |
---|---|
How is a 'population' defined? | the total group of interest |
How is a 'sample' defined? | a subgroup of the group of interest |
What is 'sampling'? | the procedure by which a sample of units or elements is selected from a population |
Who is the 'target population'? | the group to whom researchers hope to generalize their findings |
Who is the 'accessible population'? | the group of potential research participants who are actually available for a given study |
What are the four types of characteristics that define populations? Which characteristics define the target population? The accessible population? | clinical, demographic, geographic, and temporal; clinical and demographic define the target population, geographical and temporal define the accessible population |
What are the four types of probability sampling? | simple random sampling, systematic sampling, stratified sampling, and cluster sampling |
What are the three types of nonprobability sampling? | samples of convenience, snowball sampling, and purposive sampling |
What is the goal of group assignment? | to create groups that are equally representative of the entire sample; secondary goal is to develop groups of equal size |
What are some of the methods used for assignment to groups? | random assignment by individual, random assignment by block, systematic assignment, matched assignment, consecutive assignment |
What is ensured by the best assignment method? | group sizes are equal, group characteristics are similar, and group characteristics approximate the overall sample characteristics |
What is the general principle of sample size? | larger samples tend to be more representative of their parent populations than smaller samples |