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Differences between Clinicians with Different Levels of Experience

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The study of Hillerbrand and Claiborn is a 2 (level of expertise)x3 (levels of problem structure) design. 17 expert and 15 novice psychologists with good diagnostic abilities read well structured, ill structured or random structured cases. Consistency of the relevance of the information supplied varied between the cases. Relevance was the extend to which information necessary for a particular diagnosis was identified in the case. As dependent measure the accuracy of the diagnose was used, as well as the number of diagnoses, the rationale for the diagnosis and the predictions for future behaviour.

Significant differences between clinicians and novices were on ratings of their knowledge, confidence and perception of the cases’ clarity. The cognitive process however did not seem to differ. Clinical reasoning skills have been found to be present in lay-persons. It might therefore be hard to distinguish an expert from a layperson, as experience is not a sufficient condition for expertise. On the other hand you can wonder is a second or third year student is a lay-person. Certainly the training received so far will have had some impact on the cognitive processes at hand (hopefully).

The task itself is also important to consider: Whereas clinical therapists mostly have a face to face conversation with the client, in experimental studies (such as this one) the interaction is often substituted by a text about a clinical case. This way of data perception might be more appropriate for a undergraduate student, who is used to reading cases, but less used to direct therapeutic contact.

In the study of Brammer participants came from a doctoral program (n=83) or were graduate students of psychology. With the use of a computer program the structure of information exchange between the therapist and the client was simulated. After reading the case the participants could ask questions that were answered by an artificial intelligence that used pregenerated answers. As the participants asked more questions, the answers supplied additional information concerning the case. The diagnosis was sent to a panel of experts who voted the fit a the diagnosis on a 4-pooint Lickert from unlikely to definitive. The possible diagnoses were restricted to major depression, Bipolar II disorder, alcohol abuse, acute stress disorder, borderline personality disorder, nicotine dependence.

The number of diagnostic questions asked were related to correct diagnosis, as well as the level of training and the years of experience. Due to the correlational evidence no causal assumption can be made. For example the number of diagnostic question was also related to the total number of questions. Path analysis revealed there was no direct effect of level training or years of experience, instead the effect was mediated by the numbers of diagnostic questions asked.

Although the task is not a real interaction with full non-verbal communication, the interaction simulated between clinician and client was differed from a pure evaluative task. The clinician was also required to perform a skill.

The third study also compared novice and experts, but introduces intermediate level experienced clinicians as a control group. All 10 cases used as material were prerated by a panel of experts. The DSM diagnosis and the discussion was given for every case. Difficulty was enhanced by cutting back the length of the description by two thirds.

The time it took for the participants to reached a conclusion (indicate the diagnostic classification) was measured. The dependent measurement was the number of correct answers each participant gave.

The pattern that emerged form analysis can best be explained by a third-degree polynomial function. Therapists without any experience start of giving about 40% correct answers. As experience increases a decline in the percentage of correct answers is visible (less then 30% in between the second and third year of inexperience). The curve then mounts again and nears asymptotic level at about 40% correct answers.

Both experts and novice took longer to come to a conclusion than psychologists of intermediate level. This pattern also emerged in the previous study where the number of (diagnostic) questions was related to categorization quality.

Other studies who compared sub experts and experts in their cognitive structure of decision making found that there was only a difference, when time was limited. This might be the case on a face to face interaction, when decisions to pursue a specific topic have to be taken during the interaction. It might well be that the sub experts are equally able to judge the criterions of mental illness in a written form but would fail to achieve this knowledge in a real life interaction, because they do not have the conversational skills necessary.

I believe that the most important factor is to have a clear understanding of the scientific knowledge of a specific illness and be able to get all related information necessary from the client. This might be easier with a well-structured problem than with a difficult case including multiple comorbid illnesses, because the possible causal relations are much not too complex.

This hypothesis is also supported by the findings of the study of Brammer, where the quality of the diagnosis was related to the numbers of diagnostic questions asked. The difference between experts and novices can be found in the process of information gathering, rather than evaluation of the acquired data. Training new therapists might indeed by quite straightforward teaching them to ask more questions and shape the questions in a way so that the answer yields diagnostic value.

I imagine standing in china in front of a coke-vending machine. If I am an expert (and if I know Chinese) I know which button to push to get the coke. The way I see it giving cases to lay-persons is like telling exactly which button to push. Taking out the coke is easy and I do not expect Chinese and Europeans to do that differently. So the most important thing, the general background knowledge, that makes you remember to ask about manic episodes when hearing of depression, is not considered in these studies. The crucial questions to study how clinical psychologists make diagnostic classifications, might not be the ones that are asked, but those that are not asked.

Written by Martin Metzmacher

October 3, 2008 at 3:09 pm

The Influence of Aging Self-Stereotypes on Strategy Change from Goal Assimilation to Goal Accommodation

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The processes of goal assimilation and goal accommodation refer to different strategies in dealing with goals, that have become unavailable or extremely difficult to reach. Whereas the process of assimilation can be seen as a more active approach to reach a goal, accommodation refers to a more passive, internal cognitive process that changes the valence of goals. Thus the location of the focus on where to find a solution for a given problem differs for those two strategies: Whereas assimilation directs the focus towards the external world, accommodation directs the focus on the internal world.

Goal assimilation provides persistence by adjusting the strategy to reach a goal in changing environments. However goals might become unreachable or so difficult to reach that the amount of energy spent is in no relation to the possible benefits. At that point goal accommodation starts to change the underlying valence of the goal structure. The changed structure will then provide different motivation patterns that are more ecological in the perspective of the changed environment. In that sense it helps people to retain a sense of control and keeps them moving forward.

If both processes are needed for a healthy development of an individual (as has been suggested recently), there must be a critical point in time during which goal assimilation is abandoned and goal accommodation starts. This is the point at which the internal, subjective heuristics detect that for personal health, safety, happiness, etc. it is better to accommodate than assimilate a specific goal. Finding variables to predict this point in time might be very helpful in order to build a good model of goal strategies. A simple decision heuristic could look something like that:

Expected utility – Expected energy = Motivation (X)

whereas Expected utility is defined as personal value*chance of goal achievement.

As long as the motivation (X) remains positive, the course of action is “business as usual”. When the internal check reveals that the X (motivation) has become negative, the alarm rings and the assimilation process is made to check for different solutions to the equation, firstly concerning the expected energy needed for goal achievement (for example finding an easier way of achieving something by asking someone else to help). If no possible solution is found to the equation that renders X positive, the process of accommodation is activated. It checks if the variable “Goal achievement” can be redefined in such a way as to make X positive. Changing the goal valence might actually take some time and so accommodation starts working on the goal valence until motivation can be restored. This implies that there might be a period of temporary stop within the system, when there is not enough motivation to pursue a goal.

However the heuristics depend on the assumptions made by different processes and are therefore subject to possible biases. The self-view might be one of those processes that influence the information on which the heuristic decision is based. Especially for older people self-stereotyping might be an influencing factor in making the switch from goal assimilation to goal accommodation. Self-stereotyping refers to the process of applying a stereotype to the own self. In this regard it is important to differentiate between implicit and explicit stereotypes. It has been shown with many different implicit stereotypes that they are active in members of the stereotyped group on an implicit level, even if they can not be found using explicit experimental paradigms. This might be especially true for aging stereotypes, as one study reviewing the correlation between explicit and implicit beliefs found the lowest correlation between explicit and implicit beliefs on aging beliefs. One possible explanation could be that aging stereotypes are internalized during the whole life, from very early on. Those implicit knowledge structures might be difficult to access explicitly in later life. This would also imply that implicit aging stereotype are resistant to change. Implicit stereotypes have consistently shown to influence old people’s behaviour, such as their performance on a memory tests. The predominant (implicit) stereotype in the western world is that aging is a bad thing, that old people are weak and have decreased cognitive an physical abilities. How could such cognitions implicitly influence behaviour?

Let’s first have a look at the left part of the equation “Expected utility”. Older people have less time to live, so the expected utility of a goal, in which value accumulates with time, should be lower. For example if you feel that death is waiting around the corner, you might not be so motivated to stop smoking or put on sunscreen, because the possibility that you will earn the fruits of the seeds planted is very low, therefore expected value is low. Since you might already have gone through a lot of episodes of goal valence change, some goals will not be interesting anymore right from the start, like drinking and dancing all night in the club. In that way the valence of all goals are changed, as you go along, until they do not prove problematic anymore. This could also explain, why life satisfaction remains quite constant in elderly people: Since most goals have been accommodated there are not so many things to be depressed about anymore. Another point would be the expected possibility to reach a specific goal. Self-stereotyping might make it harder to imagine specific outcomes, that are not conform to the stereotype. This could lead to an underestimation of the chance of reaching a goal.

Now let’s turn to the right side of the equation that reads “Energy needed”. The amount of energy that can be invested in the achievement of any given goal is limited by the resources available, which change during lifetime. Usually when we are young we have a lot of time, physical and mental strength and a good social network. Those resources might decrease when we grow older (or am I just stereotyping?). Thus goals that require those resources become harder to reach. For some goals a minimum of a specific resource is necessary, but in most cases a lack of resources can be compensated by other resources. However, exchange of resources is probably not 1:1 and the price you pay might be related to how many resources you are missing. For example if you want to walk somewhere, but you are very slow at foot and you do not have time, you can take a taxi. But that costs you money. The slower you get, the less time you have, the more money general transport will cost you. Taking a taxi once a week to visit someone in a different city might be okay with your pool of resources, but taking a taxi several times a day, for example to go to the letterbox, might not be okay. However this could be compensated by having a good social network, someone who brings the mail along…The point I want to make is this: Resources can be exchanged, but with growing age there might be tasks, especially those that rely heavily on depleted resources, that become extremely costly. Thus the goal might still be very valuable to you, but the costs too high, which will decrease motivation. As different streams of resources become diminished there might also be a problem with choices. If you have plenty of resources available to you there might be a lot of ways in which you can assimilate a goal, thus you have a lot of opportunities to reach your goal in a different way. When your resources become more concentrated in one dimension (for example you can barely think, move, have no friends, but a few million dollars left) it might be harder to identify different solutions to the problem, or there might be less solutions available to you.

Thus having less resources available might prompt you to make the switch earlier on. The aging stereotype might suggest that one has less resources available than actually is the case. It might also be the case that the aging stereotype reduces the positive bias that people normally have about their own resources. On top of that, solutions to the motivation-equation that do not fit stereotypical behaviour of elderly people might not reach consciousness. In the same light the process of accommodation might be more stereotypical for elderly people, and thus more accessible. Over time, it might become the predominant process.

So can we propose some kind of action that would optimize the process of goal optimization and goal accommodation? The process itself should, in my view, not be the target of any change. However one could look at the implicit self-stereotype and see if it is a protective factor, by holding back older people to launch dangerous endeavors, or if it is holding them back to live a fulfilled life. Some studies have lately suggested that implicit attitudes might be open to change, for example using the AAT. Systematic search patterns for available resources and possible causes of action could also contribute to cancel out the negative side-effects of self-stereotyping in older people.

Supplementary

I would like to finish with a slightly different, but related thought, that came to my mind while writing the essay. Most old people explain that with old age they come to understand what is really important to them. However there is an alternative explanation to the change in goal valence suggested by the heuristic model. Imagine that you perceive yourself doing something. You might infer that you are actually motivated to do so, and even more if there are obstacles to your goal that you have to overcome. When you are old, activities usually bear more obstacles than before and the total range of activities is limited. Thus the perceived motivation (and probably the increased goal value) might be due to the obstacles you encounter and not to some late insight into the own emotions.

Written by Martin Metzmacher

September 30, 2008 at 9:56 pm

The descriptive approach of the DSM – why clinicians love it – and don’t adhere to it anyway

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In medicine, diseases are classified according to the physiological problem that is presumed to have caused the disease. Classification is guided by advanced biological and chemical theories that have proven to have explanatory value. For mental illnesses that is a different story, because the working mechanism is mostly unknown and there is no unified scientific framework that can explain the abnormal processes. Mental health professionals for different schools might explain any given symptom according to a different theory. In that light the DSM was created to be purely atheoretical and give a minimal framework on which everyone involved could agree upon. The resulting manual has helped communication about mental illnesses and has fostered comparable research in the field of mental health. However it is questionable if the structure of the DSM is compatible with the reality of humans, who (for the most) are driven by the unstoppable urge to make sense of their environment. Indeed it was found in many studies that therapists often classify without adhering to the specific rules laid out by the DSM. They are guided by internal rules, that work in a different way than the DSM checklist. For example therapists regard some symptoms as more important for a specific diagnose than others (concept of centrality). The DSM on the other hand usually assigns equal weights to all factors. Because the concept of centrality has profound influence on memory and other cognitive processes the therapist’s personal theory plays an important role in the classification. I believe that the DSM should be regarded as a tool supporting communication that allows discussion about the different theories at hand. It can and will not replace the theories people have. If a theory based classification system is available (for a specific disease) it should be used next to or instead of the DSM.

Written by Martin Metzmacher

September 26, 2008 at 10:01 am