Occam’s Razor and Childhood Behavior Disorders in DSM 5
A Critique of Disruptive Mood Dysregulation Disorder Proposed for DSM 5
Posted Jul 29, 2012
In the wake of the collapse of defiant misbehaviors as childhood precursors or expressions of bipolar disorder, psychiatrists must again decide how to organize and understand irritable and willful misbehavior in childhood. The decision has increased urgency because of the pressure to complete and publish DSM 5. Among the diagnoses that have been put forth to capture childhood misbehavior are Oppositional-Defiant Disorder (ODD), Disruptive Mood Dysregulation Disorder (DMDD), Attention-Deficit Hyperactivity Disorder (ADHD), Child Behavior Checklist Dysregulation Profile (CBCL-DP), and Intermittent Explosive Disorder.
Althoff recommends using Occam’s razor to classify these various disorders (Althoff, R., Dysregulated Children Reconsidered, JAACAP, 49: 302, April 2010). The term ”Occam’s Razor” was first used in 1852 and referred back to principles attributed to William of Occam (1285-1349). Occam’s razor refers to the preference of simpler explanations over more complex explanations. Occam’s razor is not a rule of logic and it is not a scientific finding. It is most often used by scientists and theoreticians to assist in deciding between competing theories for the same phenomenon. The theories remain to be proven on other grounds. For example, Ptolemy’s view of the solar system in which the sun and planets go around the earth is more complex than the Copernican view which has the sun at the center of the solar system. Thus, according to Occam’s razor, the Copernican theory is preferable (Wikipedia, Occam’s Razor http://en.wikipedia.org/wiki/Occam's_razor). Of course there are times in which a more complex explanation might be preferable because the more complex explanation seems to provide a better description of the phenomenon. For example, the currently accepted, but more complex, theory of light as waves and particles is preferable to the outmoded, but simpler, theory of light as just waves. Light as both waves and particles better fits scientific experiments about light.
In psychiatry and clinical work, Occam’s razor is often invoked when a single disease can explain a lot of medical symptoms in preference to several diseases to explain several medical symptoms. Althous offers the example of uveitis (an inflammation of the eye) alone as due to trauma, skin rash alone as due to dermatitis, and swollen joint alone as due to trauma, but the three symptoms together are often found in juvenile arthritis. Combining the various symptoms under one diagnosis, Althoff believes, is a desirable clinical use of Occam’s razor (Althoff, R., Dysregulated Children Reconsidered, JAACAP, 49: 302, April 2010).
In contemporary child psychiatry there are two new proposed entities that combine elements of several well described DSM-IV disorders of childhood: ADHD, ODD, and ill-defined aspects of depression and anxiety disorders. Althous argues that these well-established disorders ought to be combined into one of the newly proposed Child Behavior Checklist dysregulation disorder (CBCL-DR) and disruptive mood dysregulation disorder (DMDD).
CBCL-DR (not under consideration by DSM-5) is a disorder based on a subset of questions of the widely used symptom inventory, the Child Behavior Checklist. Children whose parents had described them on the checklist as having attention problems, aggressive behavior, anxiety, and depression grew into adults with problems in self regulation, including problems regulating their thinking, behavior and feelings. As adult they have been characterized as severely anxious, depressed, impulsive, aggressive, and unable to pay attention. They did not have bipolar disorder as adults (Althoff, R et al., Adult Outcomes of Childhood Dysregulation, JAACAP, 49:1105, November, 2010).
DMDD (under serious consideration for inclusion in DSM-5) includes criteria such as temper tantrums three times per week, depression and irritability between the temper tantrums, onset between the ages of 6 years and ten years, and no episodes of mania. In an important longitudinal study, these children did not develop bipolar disorder but many were depressed. The majority of the children also had ADHD and Oppositional Defiant Disorder (Stringaris, A., et al., Pediatric Bipolar Disorder Versus Severe Mood Dysregulation, JAACAP 49: 397, April, 2010).
Oppositional defiant disorder is an easily diagnosed DSM-IV disorder of children and adolescents that essentially consists of eight possible symptoms of which four must be simultaneously present to make the diagnosis. Among the eight symptoms are often loses temper, often argues with adults, and often is angry and resentful. In a longitudinal study, Stringaris et al enhanced our understanding of the significance of the disorder with the finding that different symptoms of ODD had different out comes three years later in children and adolescents. The symptoms of ODD were divided into three groups: 1) irritable symptoms; 2) headstrong symptoms, and 3) hurtful symptoms. The irritable symptoms were temper outbursts, easily annoyed, and angry and resentful. The headstrong symptoms were argues with grownups, ignores rules, and blames others for mistakes and behavior. The hurtful symptoms were spitefulness and vindictiveness.
Three years later the irritable symptoms were associated with depression and anxiety, the headstrong symptoms were associated with attention deficit hyperactivity disorder, and the hurtful behaviors were associated with conduct disorder. Thus, the diagnosis of oppositional defiant disorder has an array of symptoms that are associated with a variety of outcomes (Stringris, A. et al., What’s in a disruptive disorder? Temperamental antecedents of oppositional defiant disorder. JAACAP 49:474, May 2010; Stringaris, A. et al, Longitudinal outcome of youth oppositionality: irritable, headstrong and hurtful behaviors have distinctive predictions. JAACAP 48: 404, April 2009).
ADHD is a well known diagnosis. It is more than simple hyperactivity; it includes difficulties with organization, memory, and impulsivity. These patients often seem to have obvious difficulty regulating themselves.
The current plans for DSM 5 are to retain ADHD and ODD as diagnoses and add DMDD as an additional diagnosis. Althous suggests it makes sense that many children with ADHD and ODD might be better classified by placing them in the DDMD category. He believes these children have an anxiety or depressive disorder in addition to their ADHD and ODD and uses Occam’s razor to support adding this diagnosis. Occam’s razor might well argue against the creation of an additional ill defined diagnosis to add to and supplant well studied and well established psychiatric diagnoses. DMDD duplicates ADHD plus ODD, but adds ill-defined depression or anxiety in between tantrums. If a patient with ADHD and ODD has a depressive disorder or an anxiety disorder that meets criteria for these diagnoses the anxiety or depressive disorder should be diagnosed and treated. It is not helpful to bury ill-defined aspects of these diagnoses into a new poorly understood diagnosis: DMDD. DMDD has the potential to sow a great deal of ambiguity in clinical work. The treatments of ADHD, ODD and depression and anxiety are well described. Adding an additional diagnosis adds unnecessary ambiguity to the recognition and management of routinely encountered clinical situations.
Copyright 2012, Stuart L. Kaplan, M.D.
Stuart L. Kaplan, M.D., is the author of Your Child Does Not Have Bipolar Disorder: How Bad Science and Good Public Relations Created the Diagnosis, available on Amazon.com.