Study Design Types - Eppp Knowledge
- Which design uses preexisting groups (for example, classrooms) and compares outcomes after an intervention?
- Quasi-experimental design. Quasi-experimental designs apply interventions to intact groups, allowing comparisons in real-world settings where randomization is impractical.
- What is the defining feature of a correlational design regarding variables?
- Measures association without manipulating variables. Correlational designs examine relationships between naturally occurring variables, without intervention, to assess associations.
- Which design is primarily hypothesis-generating and strong for rich description but weak for generalization?
- Case study design. Case studies offer detailed narratives for hypothesis development but lack broad samples, limiting applicability to wider populations.
- Which option best indicates a correlational conclusion rather than a causal claim?
- "X is associated with Y". Statements of association avoid implying causation, aligning with the limitations of correlational evidence on variable relationships.
- What is the defining feature of a case study design in psychological research?
- In-depth analysis of a single person or small unit. Case studies provide detailed, qualitative insights into unique individuals or entities, facilitating deep understanding of complex phenomena.
- Which study design typically has the highest external validity: experiment, quasi-experiment, or case study?
- Quasi-experimental design (often higher than lab experiments). Quasi-experiments often occur in natural settings, enhancing generalizability to real-world populations compared to controlled lab experiments.
- Identify the design: The researcher assigns participants randomly to CBT or waitlist and compares outcomes.
- True experimental design. Random assignment to conditions in this setup ensures group equivalence, allowing causal inferences about CBT's effects.
- Which option best indicates a causal conclusion that is most defensible with random assignment?
- "X causes changes in Y". Causal claims are supported by random assignment, which controls confounds and enables defensible inferences about variable effects.
- Which design feature most directly reduces selection bias between groups?
- Random assignment. Random assignment distributes participant characteristics evenly across groups, minimizing systematic differences that could bias results.
- Identify the design: Stress and sleep are measured once and their association is analyzed.
- Correlational design. Measuring and analyzing associations without manipulation typifies correlational approaches to explore variable relationships.
- Which design is most vulnerable to confounding by third variables: correlational or experimental?
- Correlational design. Correlational designs lack manipulation and control, making them susceptible to unmeasured variables influencing observed associations.
- Which design most directly tests a treatment effect while controlling history and maturation via a control group?
- True experimental design. True experiments incorporate control groups to account for external influences like history and maturation, isolating treatment effects.
- Which design is most useful for studying rare conditions or unusual clinical presentations?
- Case study design. Case studies allow thorough exploration of infrequent events, generating hypotheses and illustrating mechanisms not feasible in larger samples.
- Which design is best for estimating the direction and strength of association between two continuous variables?
- Correlational design. Correlational designs use statistical measures like Pearson's r to quantify the strength and direction of linear relationships between continuous variables.
- What is the primary limitation of correlational designs for interpreting results?
- Cannot establish causation. Associations in correlational designs may result from third variables or reverse causality, preventing definitive causal conclusions.
- What design feature is required to classify a study as a true experiment (not quasi-experimental)?
- Random assignment to conditions. Random assignment ensures groups are equivalent at baseline, minimizing confounding variables and supporting causal inferences.
- Which design element distinguishes a quasi-experiment from a correlational study when an intervention occurs?
- Quasi-experiment includes an intervention/manipulated treatment. The presence of researcher-manipulated interventions in quasi-experiments allows for some causal testing, unlike passive measurement in correlational studies.
- What is the defining feature of a quasi-experimental design compared with a true experiment?
- Lacks random assignment to conditions. Without random assignment, quasi-experimental designs use preexisting groups, which may introduce selection biases.
- Identify the design: A detailed report describes one patient's course after a novel intervention.
- Case study design. Detailed examination of a single case provides rich, contextual insights into the intervention's process and outcomes.
- Which design best addresses temporal precedence by measuring variables over time without manipulation?
- Longitudinal correlational design. Tracking variables over time in longitudinal designs establishes temporal order, aiding in assessing potential directional relationships without manipulation.
- Which design commonly uses nonequivalent groups and may add pretest measures to improve comparability?
- Quasi-experimental design. Pretest measures in quasi-experimental designs help assess and adjust for initial group differences in nonequivalent setups.
- What is the defining feature of a true experimental design regarding the independent variable?
- Researcher manipulates the independent variable. This manipulation allows for direct testing of causal effects by controlling the variable's presence or level while holding other factors constant.
- Which study design best supports a causal inference when well-controlled: experimental or correlational?
- Experimental design. Well-controlled experiments enable causal inferences through manipulation of variables and random assignment, unlike correlational designs.
- Identify the design: Two existing clinics adopt different treatments and outcomes are compared.
- Quasi-experimental design. Using preexisting clinics without random assignment introduces potential confounds but permits real-world intervention comparisons.
- Which design is most vulnerable to selection bias: experimental or quasi-experimental?
- Quasi-experimental design. Quasi-experimental designs rely on preexisting groups, increasing the risk of inherent differences affecting outcomes.