DSM-5 takes a descriptive approach to classification, basing a diagnosis on similar, observed…

DSM-5 takes a descriptive approach to classification, basing
a diagnosis on similar, observed symptoms. The descriptive approach has
advantages. Perhaps the foremost advantage is reliability. Different clinicians
are more likely to agree about a diagnosis that is based on observable
symptoms. The DSM-5 also follows a descriptive approach when grouping diagnoses
into broader categories. For example, the new diagnostic category, somatic
symptom disorders, combines psychological factors affecting other medical
conditions together with conversion disorder and other problems that involve
somatic

DSM-5 takes a descriptive approach to classification, basing
a diagnosis on similar, observed symptoms. The descriptive approach has
advantages. Perhaps the foremost advantage is reliability. Different clinicians
are more likely to agree about a diagnosis that is based on observable
symptoms. The DSM-5 also follows a descriptive approach when grouping diagnoses
into broader categories. For example, the new diagnostic category, somatic
symptom disorders, combines psychological factors affecting other medical
conditions together with conversion disorder and other problems that involve
somatic symptoms. It is hard to argue with the practical reason DSM-5 made this
change: Somatic symptom disorders all involve physical symptoms and are,
usually, treated in medical settings by medical practitioners. We do not want
you to follow DSM-5 slavishly or uncritically. Diagnostic classifications can
be based on many grounds. We decided, for example, to discuss dissociative
disorders and conversion disorder together because of their historical
(“hysteria”) and conceptual (unconscious processes) association. (We did place
psychological factors affecting other medical conditions adjacent to other
DSM-5 somatic symptom disorders to help you understand and appreciate DSM-5’s
approach.) When we teach abnormal psychology, we do a demonstration to make the
point that classifications can be based on many different criteria. We bring a
couple of dozen items from our desk, and ask students to sort them into
categories. All of the items can be grouped together as desk materials. But we
can also group them based on their function: pens, pencils, a computer
keyboard; staples, paper clips, scotch tape; scissors, a wood letter opener. Or
we can group them based on the main material in the object: pencils, letter
opener (wood); staples, paper clips, scissors (metal); computer keyboard, pens,
scotch tape (plastic). Or we can group them according to psychoanalytic theory:
pens, pencils, scissors, letter opener; everything else. (What’s the theory?
Phallic symbols!) We question DSM-5’s descriptive approach to a number of
problems (and we want you to question DSM-5, too). To offer another example,
pica, eating nonfood substances (e.g., paper) is now classified as an eating
disorder. Sure, pica involves eating issues, as do anorexia nervosa and bulimia
nervosa. But anorexia and bulimia have a lot in common. They both include major
issues with body image, often have an onset in adolescence, are much more
common among women, are influenced by cultural standards of beauty, and so on.
Pica, typically, occurs among very young children, particularly children with intellectual
disabilities or autism spectrum disorders. Is DSM-5 being too literal in
grouping these problems together based on their appearance? We think so. It is
a bit like you saying that staples, paper clips, and scissors have to go
together. They are all shiny and silver! Critical thinking requires much more
than memorization. Of course, we want you to learn about the DSM-5, but we also
want you to understand and evaluate the diagnostic system. Our goal is not to
criticize DSM-5. Our goal is to help you think more deeply about the DSM-5 and
all kinds of scientific classifications. Is Pluto a planet? Why is plasma
different from gas? Who knows? Maybe you will help to create a new, improved
version of the DSM one day. For now, just remember this: Classifying symptoms
and disorders based on their description is a reasonable approach at this point
in the evolution of the diagnosis of mental disorders. Yet, the descriptive
approach is not necessarily the best way to classify psychological problems.
And it certainly is not the only way.