Experimental Research - Lecture Notes

These flashcards cover key concepts, definitions, and critical information regarding experimental research as discussed in the lecture.

What is the purpose of experimental design?

To examine whether the independent variable (IV) is responsible for variation in the dependent variable (DV).

What is the most rigorous research design?

Experimental design.

Why are experimental designs important for social work practice?

They are used to evaluate the efficacy of treatments or interventions before involving clients.

What does R represent in experimental design notation?

Random assignment.

What does X represent in experimental design notation?

Treatment or exposure to the experimental stimulus.

What is a control group?

A group in an experiment that does not receive the treatment, used for comparison.

What is the main limitation of the one group posttest only design?

It does not provide information about where the participants started before the intervention.

What is a quasi-experimental design?

A design where the two groups are not randomly assigned, which may affect the equivalence of the groups.

What does O represent in experimental design notation?

Observation or measurement point.

What are the four threats to internal validity?

History, maturation, testing, and instrumentation.

What does attrition refer to in experimental research?

Differential dropout rates among groups of participants.

What kind of information can you obtain using a pretest/posttest design?

It can measure the difference before and after the program.

What is internal validity?

study accurately measures the effect of the independent variable without interference from external factors

What is external validity?

The extent to which study findings can be generalized to the larger population.

What are interactions with selection?

When differences in assigned groups interact with other threats to internal validity.

What is reactivity in the context of research?

A change in behavior among subjects resulting from their awareness of being observed.

What are the symbols for standing before/after an intervention in experimental design?

O for observation and X for treatment.

What is the Solomon four group design?

A design that includes four groups: two receive treatment and two do not, controlling for pretesting effects.

When should researchers consider using a control group?

To measure the effects of an intervention against a group that does not receive it.

What is a time series design in quasi-experimental research?

An approach that collects data at multiple points over time for evaluation.

What do study authors need to consider to ensure good external validity?

They must ensure the sample used is representative of the population.

What is the ethical concern regarding experimental and quasi-experimental designs?

Denying treatment to the control group could be unethical, especially if treatment benefits are not known.

Why is random assignment crucial in experimental research?

It theoretically assures equivalency between experimental and control groups.

What variations can affect the internal validity of an experimental design?

Events occurring during the study, participant changes over time, and measurement changes.

How can attrition affect the outcomes of an experiment?

If dropout rates differ between groups, the results may not be attributable to the intervention.

What determines the choice of research design to use?

The specific research question, available resources, purpose, and audience sophistication.

Why might researchers use pre-experimental designs despite their limitations?

They may be necessary when collecting pretest data is impractical or not possible.

What is the main concern with using nonrandomized designs?

They may undermine the findings due to selection biases.