Introduction to Abnormal Child and Adolescent Psychology. Robert Weis

       According to DSM-5, a mental disorder reflects a biological, developmental, or psychological dysfunction that causes disability or distress in the individual. This definition borrows from Wakefield’s notion of a harmful dysfunction.

       DSM-5 adopts a medical approach to mental disorders.

       The medical approach is limited when applied to children and adolescents because (1) we cannot always identify the underlying cause of children’s disorders, (2) many childhood disorders are best understood in an interpersonal context rather than existing only within the child, and (3) children’s behavior is best understood in terms of their social–cultural surroundings.

      How Do Psychologists Diagnose Mental Health Problems in Children?

      Each DSM-5 disorder is defined by the presence of specific signs and symptoms. A sign is an overt feature of a disorder, whereas a symptom is a subjective experience associated with a disorder. For example, a sign of depression is weight loss or sluggish movement. In contrast, a symptom of depression is a subjective lack of appetite or energy. To be diagnosed with a given disorder, the individual must have the signs and symptoms described in the manual.

      To illustrate the diagnostic approach used in DSM-5, consider the diagnostic criteria for a major depressive episode (Figure 1.1). Depression is characterized by a discrete period of time, lasting at least 2 weeks, in which a child or adolescent experiences a marked disturbance in mood. Children with depression typically experience sad, hopeless, or irritable moods most of the day and no longer engage in activities they previously enjoyed, such as spending time with family, playing games with friends, or engaging in hobbies and sports. Children with depression can also show a wide range of other cognitive, emotional, and physical problems. This mood disturbance causes distress or leads to problems at school, at home, or with peers (American Psychiatric Association, 2013).

      Figure 1.1 ■ The DSM-5 Diagnostic Approach

      Source: Reprinted with permission from the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (Copyright 2013). American Psychiatric Association. All Rights Reserved.

      Categorical Classification

      DSM-5 uses a hybrid of three different approaches to classification: (1) categorical, (2) prototypical, and (3) dimensional. Categorical classification involves dividing mental disorders into mutually exclusive groups, or categories, based on sets of essential criteria. The categorical approach is the oldest approach to classification and is used predominantly in biology and medicine. For example, in the field of biology, an animal is classified as a mammal if it (a) has vertebrae, (b) has hair, and (c) feeds its young with mother’s milk. An animal that does not possess these essential features is not a mammal. In the field of medicine, a person is diagnosed with diabetes if she has significant problems regulating her blood glucose. A person without significant blood sugar problems is not diagnosed with diabetes. Similarly, each mental disorder is defined by the presence of essential diagnostic criteria listed in DSM-5. A person without those criteria would not be diagnosed with a given disorder (Widiger & Mullins-Sweatt, 2018).

      You can see the categorical approach to classification in the diagnostic criteria for a major depressive episode. The episode has three essential features (labeled A, B, and C). All three are required for a diagnosis of major depression.

      Prototypical Classification

      Prototypical classification is based on the degree to which the individual’s signs and symptoms map onto the ideal picture or prototype of the disorder (Westen, 2012). This approach assumes that individuals with a given disorder may show some variability; not all people with the disorder will manifest it in exactly the same way. For example, if you were asked to generate a mental picture of a bird, you would likely conjure an image of a small, flying animal with a beak that looks like a sparrow or robin. It is much less likely that your initial image of a bird would be something like a penguin or ostrich. A sparrow or robin is closer to the prototype of bird than a penguin or ostrich, although the latter two animals are certainly birds.

      Similarly, DSM-5 recognizes that most people with a specific disorder show signs and symptoms similar to the prototype for that disorder; however, DSM-5 also allows for some variability in the way people can manifest these diagnostic features.

      You can see elements of the prototypical approach to classification in the DSM-5 criteria for major depression. Although there are three essential features of the disorder, children can manifest the signs and symptoms of the disorder in nine different ways. Only five of these signs or symptoms are required for the diagnosis. For example, some depressed children experience cognitive difficulties, such as problems concentrating on their schoolwork, beliefs that they are worthless, or recurrent thoughts about death. Other children with depression experience physical problems, such as decreased appetite, insomnia, and fatigue. The prototypical approach allows flexibility in the way children experience each disorder.

      Dimensional Classification

      Dimensional classification assumes that disorders fall along a continuum of severity ranging from mild to severe. It involves describing the severity of the individual’s distress and/or disability on this continuum. One advantage of dimensional classification is that it conveys more information than simple categorical or prototypical classification. For example, rather than merely diagnosing a child with autism, a clinician can describe the child as having mild impairment in social communication but severe behavioral impairment (e.g., repetitive actions and difficulty adjusting to changes in routine). A second advantage of the dimensional approach to classification is that it allows clinicians to monitor changes in children’s functioning across time. For example, a child may continue to meet diagnostic criteria for autism after several years of behavior therapy; however, his repetitive behavior might improve from “severe” to “mild.”

      Previous versions of the DSM were criticized for their exclusive reliance on the categorical and prototypical approaches to classification. Consequently, the developers of DSM-5 attempted to incorporate aspects of dimensional classification into the newest edition of the manual. Dimensional classification is most easily seen in the DSM-5 Cross-Cutting Symptom Measure, a rating scale that can be used to evaluate the severity of children’s signs and symptoms. The rating scale allows dimensional classification on 10 broad domains including physical symptoms and sleep problems, anxiety and depression, anger and irritability, and mania and psychotic symptoms. Children’s severity on each domain can be described on a 5-point continuum ranging from “none or not at all” to “severe or nearly every day.”

      Table 1.1 shows a clinician’s ratings of an adolescent using the Cross-Cutting Symptom Measure. These ratings show that the adolescent is experiencing moderate to severe problems with depressed mood and irritability but fewer difficulties with anxiety and worry. The ratings provide additional data, above and beyond the adolescent’s diagnosis, and can be used as a baseline from which to assess the youth’s progress in treatment.

      Some DSM-5 disorders also allow clinicians to provide additional information about their clients using specifiers. A diagnostic specifier is a label that describes a relatively homogeneous subgroup of individuals with the same disorder. Usually, specifiers are created based on the person’s signs and symptoms. For example, some children with ADHD are primarily hyperactive and impulsive but listen to their parents and teachers, whereas other children with ADHD daydream in class but remain quiet and still. Although all of these children are diagnosed with ADHD, clinicians might assign the specifier “predominantly hyperactive–impulsive presentation” or “predominantly inattentive