CLINICAL JUDGMENT & DECISION MAKING
Every day, psychologists make decisions that affect the lives and well-beings of other. Although, many of these decisions are routine, other are characterized by uncertainty. Clinical information is rarely perfectly reliable; the outcomes of treatment strategies are never perfectly predicable. Understanding how clinicians make decisions in the light of uncertainty has been the subject of intensive psychological research over the past few decades. The work is based mainly on the notion of bounded rationality.
“Bounded Rationality” and Judgment Heuristics:-
It is generally agreed among clinicians that more information leads to better judgment than does less information. This is one reason why new psychologist tests are being developed. However, there are inherent limitations to the amount of information that the clinicians can handle. Because, the information processing capabilities of clinicians are limited, providing them with more information may not improve their judgment. Too much information overloads their cognitive capacity, thus reducing their diagnostic accuracy.
- One way to simplify complex cognitive tasks is to rely on stereotyped cognitive strategies such as judgment heuristics. These strategy are useful way to reduce cognitive load.
- Under certain circumstances, however, they can lead decision makers astray. When this happen, judgment is biased.
- Two most frequently studied heuristics are
- “Easy-to-recall (available) events are more likely to occur than are those that are difficult to recall”.
- Clinicians are often called on to estimate probabilities. For example, they may be asked to calculate probability that certain person will attempt suicide. Using availability heuristic, clinicians attempt to recall instances when similar clients attempted suicide. The easier it is to bring such events to mind, the higher they will rate the probability that current client will commit suicide.
- Unfortunately there are exceptions. Some researchers asked clinicians to estimate the frequency of death from various diseases. They found that clinicians over estimated deaths from some diseases (heart disease, for example) and underestimated deaths from others (asthma).
- Diseases that received more coverage in journal were rated more lethal than those that received less coverage.
- The research has concluded that journal coverage makes a disease more “available” which in true, increase its subjective frequency.
Clinical judgments based solely on how closely a specific client “represents” a stereotype case can often be tracked back to the representative heuristic. Consider for example, the case of C.S (adapted from Dawes, 1988).
“C.S had troubled in 10thgrade when she failed two courses. A psychological assessment reveals superior intelligence but personality assessment showed her to be shy and introverted; she also had trouble making friends. Because C.S had no unusual ideals and did want to make friends, her psychologists predicted that her poor grades and isolation will be temporary. A few year later, C.S graduated and went on to college where she studied literature”.
Given this background, do you believe that C.S went on to a career in business or that she is a librarian? If you think that it more likely that she is librarian, you are probably engaging in representative thinking. You believe that she is a librarian because she fills your stereotype of a librarian. Your prediction is ignores the much greater base – rate probability that C.S works in business (there are many more business people than librarian). When we all know about a person is that she was shy in 10th grade; it seems rather naive to ignore the relevant base rates and predict that she is a librarian.
- The way in which a problem is stated (or framed) can affect clinical judgment. For example people have been shown to prefer a treatment with 60% probability of success to a treatment with a 40% probability of failure even though both have 60% probability of success. The only difference between the two treatments lies in the way the problem is framed.
Oskamp (1965) found that psychologists became more convinced that they understood a case as the amount of information available to them increased. However, this confidence was not reflected in their performance; more information has not improved their prediction rate.
To help improve decision making, psychologists have developed decision aids:
- Distill the combined wisdom of many clinicians into a statistical formula.
- Use the powers of computer to develop expert computer. Expert systems are computer programs that solve problems and give advice by making inferences from a database. These operate interactively. In theory at least, expert system can help the clinician.
- To structure a problem.
- Suggest potential hypotheses.
- Point out logical weaknesses.
- Evaluate decisions.
- Set of procedures for asking decisions under conditions of uncertainty.
- It proceeds by breaking down complex decisions into smaller, more tractable problems and then combining the answers to these into an overall measure of out—attractiveness. When considering a decision analysis, clinicians must consider both the probability and the utility (subjective value) of all possible outcomes. The probability is multiplied by its utility to obtain the “expected utility. The decision that leads to the highest “expected utility (probability x utility) is usually considered”.