One of the major overhauls between DSM-IV to DSM-5 was done to handle the problem of excessive comorbidity, which is when one patient is diagnosed with two or more conditions. There was a lot of this going on with DSM-IV and earlier versions. "If someone was diagnosed with one condition they were likely to also be [incorrectly] diagnosed with having a second condition," Wang explains. "A lot of patients would fall in between categories, and there was a lot of use of a category called 'not otherwise specified' [NOS]. If you have that kind of comorbidity and that kind of use of NOS, it means that the categories are not quite working for patients and clinicians."
To address this problem, which clinicians had reported for many years previously, the DSM-5 combined nearly 30 disorders, effectively reducing diagnoses, comorbidity and unhelpful NOS. Two diagnoses were eliminated entirely, and 15 were added, according to Wang.
Probably the most well-known diagnosis removed was Asperger's syndrome, which is now classified under the autism spectrum disorder (ASD) diagnosis. This change was made in response to the research and clinical findings gleaned over the course of the previous couple of decades, with autism spectrum disorder revised to encompass four previously distinguished disorders (autistic disorder, Asperger's disorder, childhood disintegrative disorder and pervasive developmental disorder not otherwise specified) [source: Autism Society].
The hope is that refining the criteria and including a severity scale will make a diagnosis more valid and reliable. However, some critics expressed concern that removing a long-held diagnosis would negatively affect patients and their families and cause confusion in the billing/treatment communities [source: Autism Research Institute].
"I know that there was a lot of deliberation about it and then a lot of questioning," Wang explains of the switch. "It's something that people are still wrestling with." However, the advocacy group Autism Speaks points out that there should not be any change in accessing services or insurance coverage if someone's diagnosis was formerly Asperger's and is now ASD.
DSM-5 has also revamped disorders into a lifespan approach. Instead of classifying certain issues as solely "childhood disorders," it discusses how they change and manifest at all stages. DSM-5 also emphasizes the importance of parents in diagnosis and treatment. Also, although many disorders were streamlined, two childhood-specific issues were added.
Disruptive mood dysregulation disorder (DMDD) describes severe, recurrent outbursts of temper that are extremely inappropriate for the situation or in level of intensity. And social communication disorder (SCD) is "characterized by a persistent difficulty with verbal and nonverbal communication that cannot be explained by low cognitive ability," according to the APA. Prior editions of DSM didn't include the appropriate treatment for these problems because they had not been completely defined and studied, and as such treatment varied and suffered [source: APA: DSM-5 and Diagnoses for Children Fact Sheet].