Explanatory Research Flashcards
Therapeutic clinical trials examine:
the effect of the variable
preventative clinical trials examine:
capability variable (procedure/agent) to reduce the risk of developing a disease
How is the design of the explanatory created?
off of the degree of experimental control (true experimental design or quasi experimental)
how subjects are assigned into groups (between-subjects design vs. within-subject design)
What is the difference between true experimental and quasi-experimental?
quasi-experimental lacks random assignment.
Describe characteristics of between-subjects designs.
- subjects randomly assigned into different groups.
- each group is exposed to a different independent variable.
- SFD - 1 independent variable
MFD - 2 or more independent variables
describe characterstics of within subject designs.
- subjects act as their own baseline
- all subjects are exposed to all of the independent variables.
What are pros of between subject - designs?
shorter duration of study and prevents carry over effects
what are cons of between subject groups?
requires larger sample sizes and validity risk from differing individual characteristics
What are the pros of within-subject groups?
can use smaller sample size and removes effects of individual effects on conditions (increases statistical power)
what are cons of within-subject groups?
takes longer to collect data
concern for carryover effects (practice, order, sequence)
What are the 2 between subjects group designs?
pretest-posttest control group designs and post-test only control group design.
what are the independent variables called in a pretest-posttest design called?
treatement arms.
When is the posttest only control group design utilized?
when pretesting is not feasible or safe.
A one way repeated measure design is a single or multi - factor experiment where one group of subjects is:
exposed to 1 or more independent variables.
With the one-way repeated measure design, what are we concerned for and what is the solution?
concern: order effect
solution: counterbalancing: washout period between conditions.
what 2 designs does a within subjects test utilize?
one way RM design and crossover design
which design is the preferred method for controlling order effects when 2 independent variables are involved?
crossover design
crossover designs can only be utilized when the subject conditions remain:
stable.