Categorical classification of children with developmental disorders should be abandoned in favor of dimensional classification
Mental health conditions are described through two classification models; the dimensional or categorical approach. The categorical model is the current “official” diagnostic method from the chapter called “diagnostic criteria and Codes” in the DSM-5 (2013). It is the simplest and most natural way of classifying mental health problems. The alternative, the dimensional model, is also described in the DSM-5 in the chapter called “Emerging Measures and Models.” This approach is most effective when classifying conditions that are not definite, without a clear boundary, and those that cannot be measured using a numerical gaging system
The question regarding which diagnostic approach is better and more reliable is an old question. While none of them is perfectly constructed, most scientists, clinicians, and researchers tend to agree that the traditional categorical classification model is less effective and should be abandoned for the wide-ranging dimensional approach. The categorical approach is associated with multiple problems and gaps that the dimensional model attempts to fill.
First, the categorical diagnostic system is relatively shallow. When using this model, you either have a developmental disorder or not. There’s no being in between. The categorical approach is compared to the traditional lighting system, where its either on or entirely off. The dimensional approach, in contrast, allows for varying degrees and severity of a condition. This model is very effective when describing development disorders because most of them are characterized by varying degrees of impairment, ranging from mild to severe. Unlike absolute conditions like pregnancy, in developmental conditions, there is a continuum ranging between a healthy individual to one who is severely impaired.
The categorical model also classifies each disorder as a different and separate condition. The reality is that mental conditions often have similar symptoms like depression and anxiety. The failure to account for the heterogeneity of symptoms in developmental disorders makes it hard to make a correct diagnosis. The dimensional approach is able to identify various features of each condition along several continuums.
The dimensional approach has been receiving a lot of support from the different teams to be made the official diagnostic model. This approach acknowledges that developmental disorders are dimensional, and a proper diagnosis, therefore, will be to describe them in a continuum, ranging from lowest/healthy to highest/ severely unhealthy. The benefit of the dimensional diagnostic model for developmental illnesses is that it seeks to increase clinical utility by eliminating artificial and clear-cut boundaries.