The diagnostic term for adjustment disorder first appeared in the DSM-III in 1980. The manual stated that the causal stressor was daily stress at a level and quality that were not necessarily "overwhelming." Psychotic reactions were eliminated, moreover, and adjustment disorder was placed in the "short-term psychotic disorder" category, thus establishing the contemporary concept of adjustment disorders. However, because its diagnostic criteria lack any description of specific symptoms other than temporal relationships with various stressors, and due to its diagnostic requirement of "not fulfilling the criteria for other psychotic diseases," adjustment disorder is often ridiculed as a "wastebasket diagnosis," and has been the subject of discussion regarding its differences from other diagnoses.
 Even when placed under similarly stressful circumstances, some people manifest symptoms severe enough to be diagnosed as adjustment disorder, while others do not. This is caused not because of vulnerability in the personality, but because of differences in their subjective experiences, an understanding which is important to the diagnosis of adjustment disorders.
 The most important disease to consider in the differential diagnosis of adjustment disorder is depression. If the number of symptoms and their duration are insufficient to make a diagnosis of depression, the DSM-5 classifies the case either as "Other specified depressive disorders" or adjustment disorder, depending on the presence of a stressor. To make a diagnosis of adjustment disorder, however, a longitudinal diagnosis that ascertains the termination of a stressor is required. Therefore, no definitive diagnosis is made at that point. On the other hand, if the condition is ongoing, symptoms tend to aggravate and persist; thus, a diagnosis of depression is most likely made.
 There is very little research into the treatment of adjustment disorder. There are few, if any, drug or non-drug therapies that show significant efficacy. It may therefore be necessary to restrict medication to a minimum. With adjustment disorder, moreover, treatment itself may also be used as a means to "gain from illness," so it is necessary to keep in mind to prevent the symptoms from lingering and becoming chronic.
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