An accurate diagnosis is wonderful thing—a giant step toward explaining what previously seemed unexplainable and starting what is very likely to be an effective treatment. An inaccurate diagnosis can be a disaster—leading not only to inappropriate medication but also to stigma, ruined self confidence, reduced ambition, needless worries, despair about the future, and a deeply injured sense of self.
Every week, I receive one or two emails describing the pain inflicted by careless diagnosis. And when I give talks, almost invariably someone in the audience (often a mental health professional) will come up afterwards to describe their own personal ordeal—being misdiagnosed, mistreated, and given up as too ill to be productive.
The diagnoses that are most often harmfully misapplied are schizophrenia, bipolar disorder, schizoaffective disorder, ADHD, and autism. The most frequent cause of over-diagnosis is a clinician jumping to a rash conclusion based on insufficient evidence. Risk factors for mislabeling on the patient side are youth, a short track record of symptom evolution, an atypical presentation, drug use, and family or environmental stress. Risk factors on the system side are evaluator inexperience, diagnostic exuberance, and external pressures (eg whether insurance, disability, or needed school services depend on having the diagnosis).
The best way for therapists to avoid mislabeling is to take more time before arriving a diagnosis- more time in each session and using many sessions whenever things are unclear. When in doubt, clinicians should use the appropriate Not Otherwise Specified Category rather than prematurely applying an incorrect and stigmatizing label. It is almost always better to under-diagnose than to overdiagnose. Once a mislabel is given, it takes on a life of its own- it is much easier to step up to a needed diagnosis than to step down from an inaccurate one.
I have heard many heartbreaking (but also heartwarming) stories of young kids who were burdened by the weight of a gloomy diagnosis, told they would require lifelong treatment, warned that they shouldn't expect too much of themselves or from life—who ignore and belie the grim prognostication and go on to help themselves and others. Needless to say, their lives would have been a lot less complicated if more time, care, and caution had gone into the initial diagnosis.
How can you tell if you (or a loved one) has been accurately diagnosed? First off-don't be too cynical. It is a mistake to try to go it alone with self diagnosis. Most often your diagnosis is accurate and you are probably in the right treatment. But always be an informed consumer- ask questions and expect straight answers. When in doubt or if things aren't working out well, get a second opinion (and sometimes a third and forth). An accurate diagnosis is a collaborative effort that is arrived at after a joint and thoughtful process and is constantly revisited as the course evolves and more information becomes available.
Unfortunately, DSM-5 will make the current problems with mislabeling much worse. Its new proposals (with the possible exception of autism) all cast a wider diagnostic net that will lead to much looser and less accurate diagnosis. Add to this that the fact that DSM-5 has badly failed its own reliability testing because its writing is so imprecise that clinicians can't agree on how to use it. In its current form, DSM-5 is not safe and its publication should be delayed to allow sufficient time for independent review, for careful editing of its imprecise language, and for retesting to ensure adequate reliability. Anything less will cause mislabeling, result in unnecessary treatment, and make things more difficult and less promising for people who deserve better.