Dimensional Approach – to classification of mental disorder

• Categorically classifying mental disorders focuses on the KIND of problem a person is experiencing.

• A dimensional approach focuses on the EXTENT in which a person has a disorder. Many disorders (especially personality disorders) are simply normal traits gone too far.

Dimensional Approach • Doesn’t place people into

diagnostic categories. • Places people in dimensions

(sometimes seen as dimensions of personality)

• Diagnosis, then, becomes not a process of deciding the presence or absence of a symptom or disorder, but rather, the degree to which particular characteristic is present.

Dimensional approach• Instead of making judgments

of "present or not?", the dimensional approach asks the question "how much?"

• Ranks disorder on a continuum based on testing following participants completing inventories (standardised testing)

• A dimension viewed as a cluster of related psychological/behavioural characteristics that occur together

Dimensional approach• Thus statistics (profiles) can

be generated for the population and

• values are compared with the statistically ‘normal’ expected values for each characteristic – e.g.

• neuroticism, psychoticism, introversion-extroversion

• novelty seeking, harm avoidance, reward dependence

• positive emotionality, negative emotionality, constraint

Grading & Transitional• Patient is profiled by grading

the severity of symptoms from a number of dimensions in comparison to the population e.g. anxiety, variations in mood, etc.

• Symptoms can be monitored over time (Transitional) – to determine the effectiveness of treatment.

Strengths• generates richer data i.e. we get

more detail of a case by case approach for individual patient’s

• A dimensional approach would be better able to capture the complexities of a person’s life that a categorical approach would miss.

• Classifies disorder on its severity (not just presence)

• Stigma’s from labeling are less likely to occur – i.e. ‘she is highly anxious’ (not she has ‘borderline personality disorder’

Weaknesses• Complexity & lack of uniformity in mental health

profession.• Particularly given the number of dimensions that

need to be rated.