how does therapy lead to change
- Conventional perspective: gradual & in proportion to intervention efforts
- How do some treatments lead to change? Largely unknown (exception: extinction-based therapy)
- Accumulating evidence for nonlinearity and chaoticity of psychotherapy dynamics
- Phase-transition-like behavior (self organization): sudden gains or losses in symptom severity
limitations of RCTs
- We don’t learn anything about change, stability and timing, and factors related to those concepts of change
- Limited external validity
- Assumes clear boundaries between clinical categories (but: comorbidity is real!)
- Expensive and time-intensive
why cant we use ANOVA in N=1
because aova does not correct for autocorelations
autocorelations
or dependency errors
tendency of measures taken closer in time to be more similar
how can we calculate the slope of the intervention phase
intervention phase = b2+b3
what approach does psychology use nomothetic or idiographic approach
nomothetic
The nomothetic approach seeks broad generalizations, while the idiographic approach aims for detailed, individualized understanding.
how does phase transition like behavior look like
there is a stable pretransition phase - then a period of instability - which leads to a posttransition stable phase
why would u want to randomise the baseline
to make sure you are seeing the effects of the treatment not random vairation, for example that the increase in well being is bcs of start of treatmnet not because its friday night
when do you use N=1 research
- To test an RCT-proven intervention in
clinical practice, with comorbid cases or rare disorders - To run a pilot study before starting a largescale RCT
- To compare participants with themselves across different phases
why would you want to compare more than the averages of the N=1 analysis
because sometimes not taking slopes intoa ccount could lead to incorect conclusions. we want to know if the slope in the treatmernt iks bigger than the slope in the baseline
what are the 2 options of analysing N=1 research
- compare the averages between the baseline, treatment, follow up…
2.a) compare end points across phases
b) compare changes across phases
Why is the variable subject needed?
Variable that determines
dependency of errors
why is the variable time needed
Variable that creates autocorrelation (errors of nearby timepoints resemble)
what is AR1
Specific model for autocorrelation
what are assumptions underlying EST methodology
- psychopathology is highly malleable
- most patients have a single disorder or can be treated as if they do
- psychological symptoms can be understood and treated in isolation from personality factors
- RCTs provide gold standard for assesing therapeutic efficacy
