LECTURE 6 NOTES Flashcards
(43 cards)
Two views of clinical prediction
- clinical intuition
- statistical prediction
Effect on prediction
- expertise
- feedback
Prediction
a judgment made about an outcome before the outcome knowledge is known
Examples of Predictions
Will Connor bedard become an elite skate in the NHL?
Will this person stuggle with clinical depression?
Profiling
Creating or writing an outline or article that describes a person
Clinical Intuition
“people with experience and expertise in the domain make intuitive prediction for individual cases” (Kim, 2017, p105)
Clinical Intuition pt 2
*Used by clinicians with a lot of experience
profiling cases
*Interview patient about life-story
*Consider important facts and make decision *Use experience and intuition to understand the
interactions between descriptive statements of the case
How useful is clinical intuition for successful diagnosis of disorders
Statistical Prediction
“prediction about a particular case are made solely on the basis of empirical evidence and/or a statistical comparison to data drawn from a large sample” (Kim, 2017, p105)
Statistical Prediction pt. 2
*Based on Empirical data set.
*Data set is usually large
*Predictions based on comparison of scores from
a patient with scores from data set
Statistical Prediction Approach In A Nutshell
Example: Minnesota Multiphasic Personality Inventory (MMPI)
*Standardized test of psychopathology *Used to diagnose personality disorders *Tested and replicated with large samples
STATISTICAL PREDICTION APPROACH IN A NUTSHELL II
Does “Mark” suffer from depression?
*Administer the MMPI to “Mark”
*“Mark” responds to items on the MMPI *Apply statistical/Mathematical formulae to compare to a standard
*Will a typical person with “Mark’s” scores on the
MMPI be clinically diagnosed with depression?
A DISCUSSION: HOW USEFUL IS STATISTICAL PREDICTION FOR SUCCESSFUL DIAGNOSIS OF DISORDERS?
Blind Empiricism
States conditions when question is useful:
*A question is useful if people’s responses to a question can predict behaviors or disorders *As long as question can make accurate predictions, question is useful even if not based on reason or on theory
Clinical vs. Statistical Prediction
Clinical
- Based on interviews
- Follow-up Questions can be asked based on responses provided by patient
- Qualitatively rich source of information
Statistical
- Based on direct reports or self- reports of patient
- Statistical comparison of patients reports to large data set
- Prediction about diagnosis based on statistical comparison with responses from large data set
WHICH IS MORE ACCURATE AT MAKING CLINICAL DIAGNOSIS:
CLINICAL INTUITION VS. STATISTICAL PREDICTION
“Mechanical prediction is typically as accurate or more accurate than clinical prediction.”
“Even though outlier studies can be found, we identified no systematic exceptions to the general superiority ( or at least material equivalence) of mechanical prediction.”
(Grove et al, 2000, p25)
The evidence suggests that mechanical prediction is superior
In the outlier studies, can any characteristics be identified that suggest an advantage for using clinical intuition over mechanical prediction?
“In seven of the eight studies, the clinicians received more data than the mechanical prediction.”
However, for most of the reported studies, “clinical predictions were outperformed by a substantially greater margin when such data was available to the clinician.”
(Grove et al, 2000, p25)
Grove et al (2000) Question
Which is more accurate: Intuition or prediction?
“mechanical predictions of human behaviors are equal or superior to clinical predictions (intuition) methods for a wide range of circumstances.” (Grove et al, 2000, p19) see abstract
Meta analysis
An analysis of several analyses that answers a specific question
How to do a meta-analysis
*Perform a literature search and identify all articles that address the question (i.e., judgment based on intuition vs. judgment based on prediction)
*Be aware of any statistical/methodological issues and apply statistical technique to compensate
*Perform the comparison test(s)
*Identified 136 studies that were suitable for the meta-analysis
*Performed the meta-analysis to identify whether intuition or prediction was superior.
Why is clinical intuition inferior to mechanical prediction
- Ignore base rates and prior probabilities
- Overreliance on the representativeness heuristic
- Overreliance on the availability heuristic
- Assign nonoptimal weights to cues
Incorrect Decisions in Predictions
Background: Hypothesis Testing
Type 1 Error
- theory is not true
- decide theory Is true
Correct Decision for Type 2
- Theory is not true
- decide theory is not true
