Normative models require the data to be linear. Each case should be weighted linearly and combined additively. That is certainly not the case in clinical settings. Not all therapists have clear guidelines for themselves on what to base a categorical decision. When comparing the data at hand they rely on statistical models that are fallible. They are subject to the same biases that “normal people” are subject to: They think that the information presented matches the diagnose even if the behaviour could be interpreted as ambiguous and that other people would consent with their diagnosis.
Unaided Categorical Psychodiagnosis is not Coherent with Normative Models
Keep reading
The Downside of the Glorious RCTs
RCTs are great and every empirical scientist loves them. Everyone? No there is a small village in the south of France…Well to be honest I believe that RCT’s are just a hype. Of course they were great in reducing a lot of statistical problems and have helped psychology to become a “respected science” and earn […]
What is Effect Size?
Effect size is a parametric test, belonging to the GLM family that allows to compare the size of an effect between two groups (or for that matter two conditions in one group). The test can be used in all kinds of research designs (experimental and non-experimental) that employ different kind of measurements or/and manipulations. Given […]
Why the CBCL’s Inter-rater Reliability is poor at the Item and Syndrome level
There seem to be no obvious methodological or statistical issues that could account for the poor inter-rater reliability. Embregts argues that informants might have a different view on presence and severity of behavioral problems depending on the frequency and quality of interaction they have with the client (“biased” data). Secondly both judges might have different […]