What constitutes empirical evidence?
observable, systematic data. Does it work? And how/why does it work
What features make a good psychological theory?
Internally consistent, measurable, supported by basic and applied research, and backed by peer-reviewed evidence.
What is a “horse race” RCT?
A randomized controlled trial comparing one full treatment to another or a control group
What can a horse race tell you?
Whether a treatment works better than another
What can’t a horse race tell you?
How or why a treatment works it doesn’t test mechanisms of change.
What is an RCT with process measures?
An outcome study that also measures psychological mechanisms of change
What does an RCT with process measures show?
Whether changes in proposed mechanisms predict symptom improvement
What are the limits of RCTs with process measures?
They show associations, not definite causation, because many variable change during therapy.
What are basic experimental studies in psychotherapy?
Lab studies testing specific components of a theory
What do basic experimental studies show?
Whether specific mechanisms cause change under controlled conditions
What is the strongest form of evidence overall?
When basic experimental findings and clinical RCT results converge to support a theory
What is observational research?
Systematically observing behavior in real or controlled settings
Strength of observational research?
Real-world relevance
Weakness of observational research?
Poor control; possible observer bias
What is a case study?
Intensive study of one individual, often used to generate hypotheses or study rare cases
Weaknesses of case studies?
Can’t generalize or determine cause and effect
What is epidemiological research?
Studies the incidence and prevalence of disorders and related risk factors in populations
What is correlational research?
Measures the relationship between variables without manipulating them
Why can’t correlation prove causation?
Because of possible third variables and directionality problems
Whats the difference between cross-sectional and longitudinal designs?
Cross-sectional = one time point; Longitudinal = follows same people over time
What is an experimental study?
A study with random assignment and manipulation of an independent variable to test causality
What is a between-subjects design?
Different groups receive different conditions
What is a within-subjects design?
The same participants experience all conditions
What is internal validity?
Confidence that changes in the dependent variable were caused by the independent variable
