The past DSM-IV criteria for IED were similar to the current criteria, however verbal aggression was not considered as part of the diagnostic criteria. The DSM-IV diagnosis was characterized by the occurrence of discrete episodes of failure to resist aggressive impulses that result in violent assault or destruction of property. Additionally, the degree of aggressiveness expressed during an episode should be grossly disproportionate to provocation or precipitating psychosocial stressor, and, as previously stated, diagnosis is made when certain other mental disorders have been ruled out, e.g., a head injury, Alzheimer's disease, etc., or due to substance abuse or medication. Diagnosis is made using a psychiatric interview to affective and behavioral symptoms to the criteria listed in the DSM-IV.

The DSM-IV-TR was very specific in its definition of Intermittent Explosive Disorder which was defined, essentially, by exclusion of other conditions. The diagnosis required:

1. several episodes of impulsive behavior that result in serious damage to either persons or property, wherein

2. the degree of the aggressiveness is grossly disproportionate to the circumstances or provocation, and

3. the episodic violence cannot be better accounted for by another mental or physical medical condition.

Psychiatrists seek to provide a medical diagnosis of individuals by an assessment of symptoms, signs and impairment associated with particular types of mental disorder. Other mental health professionals, such as clinical psychologists, may or may not apply the same diagnostic categories to their clinical formulation of a client's difficulties and circumstances. The majority of mental health problems are, at least initially, assessed and treated by family physicians (in the UK general practitioners) during consultations, who may refer a patient on for more specialist diagnosis in acute or chronic cases.

Routine diagnostic practice in mental health services typically involves an interview known as a mental status examination, where evaluations are made of appearance and behavior, self-reported symptoms, mental health history, and current life circumstances. The views of other professionals, relatives or other third parties may be taken into account. A physical examination to check for ill health or the effects of medications or other drugs may be conducted. Psychological testing is sometimes used via paper-and-pen or computerized questionnaires, which may include algorithms based on ticking off standardized diagnostic criteria, and in rare specialist cases neuroimaging tests may be requested, but such methods are more commonly found in research studies than routine clinical practice.

Time and budgetary constraints often limit practicing psychiatrists from conducting more thorough diagnostic evaluations. It has been found that most clinicians evaluate patients using an unstructured, open-ended approach, with limited training in evidence-based assessment methods, and that inaccurate diagnosis may be common in routine practice. In addition, comorbidity is very common in psychiatric diagnosis, where the same person meets the criteria for more than one disorder. On the other hand, a person may have several different difficulties only some of which meet the criteria for being diagnosed. There may be specific problems with accurate diagnosis in developing countries.

More structured approaches are being increasingly used to measure levels of mental illness.

- HoNOS is the most widely used measure in English mental health services, being used by at least 61 trusts. In HoNOS a score of 0–4 is given for each of 12 factors, based on functional living capacity. Research has been supportive of HoNOS, although some questions have been asked about whether it provides adequate coverage of the range and complexity of mental illness problems, and whether the fact that often only 3 of the 12 scales vary over time gives enough subtlety to accurately measure outcomes of treatment.

Many psychiatric disorders and some substance use disorders are associated with increased aggression and are frequently comorbid with IED, often making differential diagnosis difficult. Individuals with IED are, on average, four times more likely to develop depressive or anxiety disorders, and three times more likely to develop substance use disorders.

Bipolar disorder has been linked to increased agitation and aggressive behavior in some individuals, but for these individuals aggressiveness is limited to manic and/or depressive episodes, whereas individuals with IED experience aggressive behavior even during periods with a neutral or positive mood. In one clinical study, the two disorders co-occurred 60% of the time. Patients report manic-like symptoms occurring just before outbursts and continuing throughout. According to a study, the average onset age of IED was around five years earlier than the onset age of bipolar disorder, indicating a possible correlation between the two.

Similarly, alcohol and other substance use disorders may exhibit increased aggressiveness, but unless this aggression is experienced outside of periods of acute intoxication and withdrawal, no diagnosis of IED is given. For chronic disorders, such as PTSD, it is important to assess whether the level of aggression met IED criteria prior to the development of another disorder. In antisocial personality disorder, interpersonal aggression is usually instrumental in nature (i.e., motivated by tangible rewards), whereas IED is more of an impulsive, unpremeditated reaction to situational stress.

The person's appearance, behavior, and history, along with a psychological evaluation, are usually sufficient to establish a diagnosis. There is no test to confirm this diagnosis. Because the criteria are subjective, some people may be wrongly diagnosed.

The basis of the diagnosis is the presence of a precipitating stressor and a clinical evaluation of the possibility of symptom resolution on removal of the stressor due to the limitations in the criteria for diagnosing AD. In addition, the diagnosis of AD is less clear when patients are exposed to stressors long-term, because this type of exposure is associated with AD and major depressive disorder (MDD) and generalized anxiety disorder (GAD).

Some signs and criteria used to establish a diagnosis are important. First, the symptoms must clearly follow a stressor. The symptoms should be more severe than would be expected. There should not appear to be other underlying disorders. The symptoms that are present are not part of a normal grieving for the death of family member or other loved one.

Adjustment disorders have the ability to be self-limiting. Within five years of when they are originally diagnosed, approximately 20%–50% of the sufferers go on to be diagnosed with psychiatric disorders that are more serious.

Since the 1980s, Paula Caplan has been concerned about the subjectivity of psychiatric diagnosis, and people being arbitrarily “slapped with a psychiatric label.” Caplan says because psychiatric diagnosis is unregulated, doctors are not required to spend much time interviewing patients or to seek a second opinion. The Diagnostic and Statistical Manual of Mental Disorders can lead a psychiatrist to focus on narrow checklists of symptoms, with little consideration of what is actually causing the patient’s problems. So, according to Caplan, getting a psychiatric diagnosis and label often stands in the way of recovery.

In 2013, psychiatrist Allen Frances wrote a paper entitled "The New Crisis of Confidence in Psychiatric Diagnosis", which said that "psychiatric diagnosis… still relies exclusively on fallible subjective judgments rather than objective biological tests." Frances was also concerned about "unpredictable overdiagnosis." For many years, marginalized psychiatrists (such as Peter Breggin, Thomas Szasz) and outside critics (such as Stuart A. Kirk) have "been accusing psychiatry of engaging in the systematic medicalization of normality." More recently these concerns have come from insiders who have worked for and promoted the American Psychiatric Association (e.g., Robert Spitzer, Allen Frances). A 2002 editorial in the "British Medical Journal" warned of inappropriate medicalization leading to disease mongering, where the boundaries of the definition of illnesses are expanded to include personal problems as medical problems or risks of diseases are emphasized to broaden the market for medications.

The previous edition of the Diagnostic and Statistical Manual of Mental Disorders, DSM IV-TR, defines histrionic personality disorder (in Cluster B) as:

The DSM-IV requires that a diagnosis for any specific personality disorder also satisfies a set of general personality disorder criteria.

Despite recent initiatives to study psychopathology along dimensions of behavior and neurobiological indices, which would help refine a clearer picture of the development and treatment of externalizing disorders, the majority of research has examined specific mental disorders. Thus, best practices for many externalizing disorders are disorder-specific. For example, substance use disorders themselves are very heterogeneous and their best-evidenced treatment typically includes cognitive behavioral therapy, motivational interviewing, and a substance disorder-specific detoxification or psychotropic medication treatment component. The best-evidenced treatment for childhood conduct and externalizing problems more broadly, including youth with ADHD, ODD, and CD, is parent management training, a form of cognitive behavioral therapy. Additionally, individuals with ADHD, both youth and adults, are frequently treated with stimulant medications (or alternative psychotropic medications), especially if psychotherapy alone has not been effective in managing symptoms and impairment. Psychotherapy and medication interventions for individuals with severe, adult forms of antisocial behavior, such as antisocial personality disorder, have been mostly ineffective. An individual's comorbid psychopathology may also influences the course of treatment for an individual.

ADHD often precedes the onset of ODD, and approximately half of children with ADHD, Combined Type also have ODD. ODD is a risk factor for CD and frequently precedes the onset of CD symptoms. Children with an early onset of CD symptoms, with at least one symptom before age 10 years, are at risk for more severe and persistent antisocial behavior continuing into adulthood. Youth with early-onset conduct problems are particularly at risk for ASPD (note that an onset of CD prior to age 15 is part of the diagnostic criteria for ASPD), whereas CD is typically limited to adolescence when youth's CD symptoms begin during adolescence.

International Statistical Classification of Diseases and Related Health Problems, mostly known as "ICD", assigns codes to classify diseases, symptoms, complaints, social behaviors, injuries, and such medical-related findings.

ICD 10 classifies adjustment disorders under F40-F48 and under neurotic, stress-related and somatoform disorders.

There is a considerable personality disorder diagnostic co-occurrence. Patients who meet the DSM-IV-TR diagnostic criteria for one personality disorder are likely to meet the diagnostic criteria for another. Diagnostic categories provide clear, vivid descriptions of discrete personality types but the personality structure of actual patients might be more accurately described by a constellation of maladaptive personality traits.

"Sites used DSM-III-R criterion sets. Data obtained for purposes of informing the development of the DSM-IV-TR personality disorder diagnostic criteria."

Abbreviations used: "PPD – Paranoid Personality Disorder, SzPD – Schizoid Personality Disorder, StPD – Schizotypal Personality Disorder, ASPD – Antisocial Personality Disorder, BPD – Borderline Personality Disorder, HPD – Histrionic Personality Disorder, NPD – Narcissistic Personality Disorder, AvPD – Avoidant Personality Disorder, DPD – Dependent Personality Disorder, OCPD – Obsessive-Compulsive Personality Disorder, PAPD – Passive-Aggressive Personality Disorder."

Impulse-control disorders have two treatment options: psychosocial and pharmacological. Treatment methodology is informed by the presence of comorbid conditions.

Pyromania is best prevented by parents taking the time to educate their children on fire safety and the dangers of fires. Parents should also keep all fire lighting devices out of reach of children and any teenagers to reduce the risk of their starting any fires .

ASPD commonly coexists with the following conditions:

When combined with alcoholism, people may show frontal function deficits on neuropsychological tests greater than those associated with each condition.

The appropriate treatment for pyromania varies with the age of the patient and the seriousness of the condition. For children and adolescents treatment usually is cognitive behavioral therapy sessions in which the patient’s situation is diagnosed to find out what may have caused this impulsive behavior. Once the situation is diagnosed, repeated therapy sessions usually help continue to a recovery . Other important steps must be taken as well with the interventions and the cause of the impulse behavior. Some other treatments measures include parenting training, over-correction/satiation/negative practice with corrective consequences, behavior contracting/token reinforcement, special problem-solving skills training, relaxation training, covert sensitization, fire safety and prevention education, individual and family therapy, and medication. The prognosis for recovery in adolescents and children who suffer from pyromania depends on the environmental or individual factors in play, but is generally positive. Pyromania is generally harder to treat in adults, often due to lack of cooperation by the patient. Treatment usually consists of more medication to prevent stress or emotional outbursts in addition to long-term psychotherapy . In adults, however, the recovery rate is generally poor and if an adult does recover it usually takes a longer period of time .

Complications of late Parkinson's disease may include a range of impulse-control disorders, including eating, buying, compulsive gambling and sexual behavior. One study found that 13.6% of Parkinson's patients exhibited at least one form of ICD. There is a significant co-occurrence of pathological gambling and personality disorder, and is suggested to be caused partly by their common "genetic vulnerability". The degree of heritability to ICD is similar to other psychiatric disorders including substance abuse disorder. There has also been found a genetic factor to the development of ICD just as there is for substance abuse disorder. The risk for subclinical PG in a population is accounted for by the risk of alcohol dependence by about 12-20% genetic and 3-8% environmental factors. There is a high rate of comorbidity between ADHD and other impulse-control disorders.

Currently, genetic research for the understanding of the development of personality disorders is severely lacking. However, there are a few possible risk factors currently in discovery. Researchers are currently looking into genetic mechanisms for traits such as aggression, fear and anxiety, which are associated with diagnosed individuals. More research is being conducted into disorder specific mechanisms.

Because of reduced levels of trust, there can be challenges in treating PPD. However, psychotherapy, antidepressants, antipsychotics and anti-anxiety medications can play a role when an individual is receptive to intervention.

Since people buying more than they need is usual and accepted, even the most excessive behaviour takes a long time before being considered pathological. Shopping addiction generally manifests between 20–30 years old,

but is not usually detected until several years after, when the addiction has led the person to ruin and bankrupt.

There are usually two stages in coping with the problem. First, people around the addict or the health or social services detect the problem and try to treat it. When, because of the seriousness of the case, it is not possible to solve it in this way, specialised professionals, such as psychologist or psychiatrics, take part. The diagnosis and evaluation of shopping addiction is based on the analysis of confirmed behaviours and their consequences. Specific tests or questionnaires, as the FACC-II (Questionnaire on the psychological aspects of consumer addiction, debt and personal spending habits) are also used. These specific questionnaires or tests are useful in the diagnosis and evaluation of shopping addiction problems, and to drive the therapies in a proper way. FACC-II is one of the most specific and widest. The Edwards Scale is another approach which measures the tendency to compulsively buy. All these resources, as well as personal interviews of the addict and people who surround them, reports and other documents, enable knowledge of when people buy, what they buy and the methods of payment used.

Psychiatrist Kantor suggests a treatment approach using psychodynamic, supportive, cognitive, behavioral and interpersonal therapeutic methods. These methods apply to both the Passive–aggressive person and their target victim.

Treatment involves becoming conscious of the addiction through studying, therapy, group work, etc...

Research done by Michel Lejoyeux and Aviv Weinstein suggests that the best possible treatment for CB is through cognitive behavioral therapy. They suggest that a patient first be "evaluated for psychiatric comorbidity, especially with depression, so that appropriate pharmacological treatment can be instituted." Their research indicates that patients who received cognitive behavioral therapy over 10 weeks had reduced episodes of compulsive buying and spent less time shopping as opposed to patients who did not receive this treatment (251).

Lejoyeux and Weinstein also write about pharmacological treatment and studies that question the use of drugs on CB. They declare "Few controlled studies have assessed the effects of pharmacological treatment on compulsive buying, and none have shown any medication to be effective" (252). The most effective treatment is to attend therapy and group work in order to prevent continuation of this addiction.

Selective serotonin reuptake inhibitors such as fluvoxamine and citalopram may be useful in the treatment of CBD, although current evidence is mixed. Opioid antagonists such as naltrexone and nalmefene are promising potential treatments for CBD. A review concluded that evidence is limited and insufficient to support their use at present, however. Naltrexone and nalmefene have also shown effectiveness in the treatment of gambling addiction, an associated disorder.

No true psychiatric medications are prescribed for factitious disorder. However, selective serotonin reuptake inhibitors (SSRIs) can help manage underlying problems. Medicines such as SSRIs that are used to treat mood disorders can be used to treat FD, as a mood disorder may be the underlying cause of FD. Some authors (such as Prior and Gordon 1997) also report good responses to antipsychotic drugs such as Pimozide. Family therapy can also help. In such therapy, families are helped to better understand patients (the individual in the family with FD) and that person's need for attention.

In this therapeutic setting, the family is urged not to condone or reward the FD individual's behavior. This form of treatment can be unsuccessful if the family is uncooperative or displays signs of denial and/or antisocial disorder. Psychotherapy is another method used to treat the disorder. These sessions should focus on the psychiatrist's establishing and maintaining a relationship with the patient. Such a relationship may help to contain symptoms of FD. Monitoring is also a form that may be indicated for the FD patient's own good; FD (especially proxy) can be detrimental to an individual's health—if they are, in fact, causing true physiological illnesses. Even faked illnesses/injuries can be dangerous, and might be monitored for fear that unnecessary surgery may subsequently be performed.

The word '' means 'substitute'. It is coded in the DSM-IV under Factitious Disorder NOS (not otherwise specified). Münchausen by proxy is the involuntary use of another individual to play the patient role. For example, false symptoms are produced in children by the caregivers or parents, to produce the appearance of illness, or they may give misleading medical histories about their children. The parent may falsify the child's medical history or tamper with laboratory tests to make the child appear sick. Occasionally, in Münchausen by proxy, the caregiver actually injures the child or makes it sick to ensure that the child is treated. For instance, a father whose son is coeliac might knowingly introduce gluten into the diet. Such parents may be validated by the attention that they receive from having a sick child.

SPD can be first apparent in childhood and adolescence with solitariness, poor peer relationships, and underachievement in school. This may mark these children as different and make them subject to teasing.

Being a personality disorder, which are usually chronic and long-lasting mental conditions, schizoid personality disorder is not expected to improve with time without treatment; however, much remains unknown because it is rarely encountered in clinical settings.

The consequences of oniomania, which may persist long after a spree, can be devastating, with marriages, long-term relationships, and jobs all feeling the strain. Further problems can include ruined credit history, theft or defalcation of money, defaulted loans, general financial trouble and in some cases bankruptcy or extreme debt, as well as anxiety and a sense of life spiraling out of control. The resulting stress can lead to physical health problems and ruined relationships, or even suicide.