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.

Psychosis as a symptom of a psychiatric disorder is first and foremost a diagnosis of exclusion. So a new-onset episode of psychosis "cannot" be considered to be a symptom of a psychiatric disorder until other relevant and known medical causes of psychosis are excluded, or ruled out. Many clinicians improperly perform, or entirely miss this step, introducing avoidable diagnostic error and misdiagnosis.

An initial assessment includes a comprehensive history and physical examination. Although no biological laboratory tests exist which confirm schizoaffective disorder, biological tests should be performed to exclude psychosis associated with or caused by substance use, medications, toxins or poisons, surgical complications, or other medical illnesses. Since non-medical mental health practitioners are not trained to exclude medical causes of psychosis, people experiencing psychosis should be referred to an emergency department or hospital.

Delirium should be ruled out, which can be distinguished by visual hallucinations, acute onset and fluctuating level of consciousness, indicating other underlying factors which includes medical illnesses. Excluding medical illnesses associated with psychosis is performed by using blood tests to measure:

- Thyroid-stimulating hormone to exclude hypo- or hyperthyroidism,

- Basic electrolytes and serum calcium to rule out a metabolic disturbance,

- Full blood count including ESR to rule out a systemic infection or chronic disease, and

- Serology to exclude syphilis or HIV infection.

Other investigations which may be performed include:

- EEG to exclude epilepsy, and an

- MRI or CT scan of the head to exclude brain lesions.

Blood tests are not usually repeated for relapse in people with an established diagnosis of schizoaffective disorder, unless there is a specific "medical" indication. These may include serum BSL if olanzapine has previously been prescribed, thyroid function if lithium has previously been taken to rule out hypothyroidism, liver function tests if chlorpromazine has been prescribed, CPK levels to exclude neuroleptic malignant syndrome, and a urinalysis and serum toxicology screening if substance use is suspected. Assessment and treatment may be done on an outpatient basis; admission to an inpatient facility is considered if there is a risk to self or others.

Because psychosis may be precipitated or exacerbated by common classes of psychiatric medications, such as antidepressants, ADHD stimulant medications, and sleep medications, prescribed medication-induced psychosis should be ruled out, particularly for first-episode psychosis. This is an essential step to reduce diagnostic error and to evaluate potential medication sources of further patient harm. Regarding prescribed medication sources of patient harm, Yale School of Medicine Professor of Psychiatry Malcolm B. Bowers, Jr, MD wrote:

Illicit drugs aren't the only ones that precipitate psychosis or mania—prescribed drugs can too, and in particular, some psychiatric drugs. We investigated this and found that about 1 in 12 psychotic or manic patients in an inpatient psychiatric facility are there due to antidepressant-induced psychosis or mania. That's unfortunate for the field [of psychiatry] and disastrous for some of our patients.

Substance-induced psychosis should also be ruled out. Both substance- and medication-induced psychosis can be excluded to a high level of certainty while the person is psychotic, typically in an emergency department, using both a

- Broad spectrum urine toxicology screening, and a

- Full serum toxicology screening (of the blood).

Some dietary supplements may also induce psychosis or mania, but cannot be ruled out with laboratory tests. So a psychotic person's family, partner, or friends should be asked whether he or she is currently taking any dietary supplements.

Common mistakes made when diagnosing psychotic patients include:

- Not properly excluding delirium,

- Missing a toxic psychosis by not screening for substances "and" medications,

- Not appreciating medical abnormalities (e.g., vital signs),

- Not obtaining a medical history and family history,

- Indiscriminate screening without an organizing framework,

- Not asking family or others about dietary supplements,

- Premature diagnostic closure, and

- Not revisiting or questioning the initial diagnostic impression of primary psychiatric disorder.

Only after these relevant and known causes of psychosis have been ruled out can a psychiatric differential diagnosis be made. A mental health clinician will incorporate family history, observation of a psychotic person's behavior while the person is experiencing active symptoms, to begin a psychiatric differential diagnosis. Diagnosis also includes self-reported experiences, as well as behavioral abnormalities reported by family members, friends, or significant others. Mistakes in this stage include:

- Not screening for dissociative disorders. Dissociative identity disorder and psychotic symptoms in schizoaffective disorder have considerable overlap, yet a different overall treatment approach.

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.

There is little data on the effects of screening the general population on the ultimate rate of suicide. Screening those who come to the emergency departments with injuries from self harm have been shown to help identify suicide ideation and suicide intention. Psychometric tests such as the Beck Depression Inventory or the Geriatric Depression Scale for older people are being used. As there is a high rate of people who test positive via these tools that are not at risk of suicide, there are concerns that screening may significantly increase mental health care resource utilization. Assessing those at high risk however is recommended. Asking about suicidality does not appear to increase the risk.

A diagnostic assessment may be conducted by a suitably trained general practitioner, or by a psychiatrist or psychologist, who records the person's current circumstances, biographical history, current symptoms, and family history. The broad clinical aim is to formulate the relevant biological, psychological, and social factors that may be impacting on the individual's mood. The assessor may also discuss the person's current ways of regulating mood (healthy or otherwise) such as alcohol and drug use. The assessment also includes a mental state examination, which is an assessment of the person's current mood and thought content, in particular the presence of themes of hopelessness or pessimism, self-harm or suicide, and an absence of positive thoughts or plans. Specialist mental health services are rare in rural areas, and thus diagnosis and management is left largely to primary-care clinicians. This issue is even more marked in developing countries. The mental health examination may include the use of a rating scale such as the Hamilton Rating Scale for Depression or the Beck Depression Inventory or the Suicide Behaviors Questionnaire-Revised. The score on a rating scale alone is insufficient to diagnose depression to the satisfaction of the DSM or ICD, but it provides an indication of the severity of symptoms for a time period, so a person who scores above a given cut-off point can be more thoroughly evaluated for a depressive disorder diagnosis. Several rating scales are used for this purpose.

Primary-care physicians and other non-psychiatrist physicians have more difficulty with underrecognition and undertreatment of depression compared to psychiatric physicians, in part because of the physical symptoms that often accompany depression, in addition to the many potential patient, provider, and system barriers that the authors describe. A review found that non-psychiatrist physicians miss about two-thirds of cases, though this has improved somewhat in more recent studies.

Before diagnosing a major depressive disorder, in general a doctor performs a medical examination and selected investigations to rule out other causes of symptoms. These include blood tests measuring TSH and thyroxine to exclude hypothyroidism; basic electrolytes and serum calcium to rule out a metabolic disturbance; and a full blood count including ESR to rule out a systemic infection or chronic disease. Adverse affective reactions to medications or alcohol misuse are often ruled out, as well. Testosterone levels may be evaluated to diagnose hypogonadism, a cause of depression in men. Vitamin D levels might be evaluated, as low levels of vitamin D have been associated with greater risk for depression.

Subjective cognitive complaints appear in older depressed people, but they can also be indicative of the onset of a dementing disorder, such as Alzheimer's disease. Cognitive testing and brain imaging can help distinguish depression from dementia. A CT scan can exclude brain pathology in those with psychotic, rapid-onset or otherwise unusual symptoms. In general, investigations are not repeated for a subsequent episode unless there is a medical indication.

No biological tests confirm major depression. Biomarkers of depression have been sought to provide an objective method of diagnosis. There are several potential biomarkers, including Brain-Derived Neurotrophic Factor and various functional MRI techniques. One study developed a decision tree model of interpreting a series of fMRI scans taken during various activities. In their subjects, the authors of that study were able to achieve a sensitivity of 80% and a specificity of 87%, corresponding to a negative predictive value of 98% and a positive predictive value of 32% (positive and negative likelihood ratios were 6.15, 0.23, respectively). However, much more research is needed before these tests could be used clinically.

Healthcare providers may screen patients for depression using a screening tool, such as the Patient Healthcare Questionnaire-2 (PHQ-2).

To diagnose a major depressive episode, a trained healthcare provider must make sure that:

- The symptoms do not meet the criteria for a mixed episode.

- The symptoms must cause considerable distress or impair functioning at work, in social settings or in other important areas in order to qualify as an episode.

- The symptoms are not due to the direct physiological effects of a substance (e.g., abuse of a drug or medication) or a general medical condition (e.g., hypothyroidism).

- Other than in the case of severe symptoms (severely impaired functioning, severe preoccupation with worthlessness, ideas of suicide, delusions or hallucinations or psychomotor retardation).

In 2016, the United States Preventive Services Task Force (USPSTF) recommended screening in the adult populations with evidence that it increases the detection of people with depression and with proper treatment improves outcomes. They recommend screening in those between the age of 12 to 18 as well.

A Cochrane review from 2005 found screening programs do not significantly improve detection rates, treatment, or outcome.

The most widely used criteria for diagnosing schizoaffective disorder are from the American Psychiatric Association's "Diagnostic and Statistical Manual of Mental Disorders-5".

The DSM-IV schizoaffective disorder definition was plagued by problems of being inconsistently (or unreliably) used on patients; when the diagnosis is made, it doesn't stay with most patients over time; and it has questionable diagnostic validity (that is, it doesn't describe a distinct disorder, nor predict any particular outcome). These problems have been slightly reduced (or "modestly improved") in the DSM-5 according to Carpenter.

When psychotic symptoms are confined to an episode of mania or depression (with or without mixed features), the diagnosis is that of a “psychotic” mood disorder, namely either bipolar disorder or major depression). Only when psychotic states persist in a sustained fashion for two weeks or longer without concurrent affective symptoms is the diagnosis schizoaffective disorder or schizophrenia.

The second cardinal guideline in the DSM-5 diagnosis of schizoaffective disorder is one of timeframe.

These two changes are intended by the DSM-5 workgroup to accomplish two goals:

- Increase the diagnosis' consistency (or reliability) when it is used;

- Significantly decrease the overall use of the schizoaffective disorder diagnosis.

If the schizoaffective diagnosis is used less often, other diagnoses (like psychotic mood disorders and schizophrenia) are likely to be used more often; but this is hypothetical until real-world data arrive. Validity problems with the diagnosis remain and await further work in the fields of psychiatric genetics, neuroimaging, and cognitive science that includes the overlapping fields of cognitive, affective, and social neuroscience, which may change the way schizoaffective disorder is conceptualized and defined in future versions of the DSM and ICD.

Questionnaires and checklists such as the Beck Depression Inventory or the Children's Depression Inventory can be used by a mental health provider to help detect, and assess the severity of depression. The Seasonal Pattern Assessment Questionnaire can be used to screen for seasonal affective disorder. Semi structured interviews such as the Kiddie Schedule for Affective Disorders and Schizophrenia (KSADS) and the Structured Clinical Interview for DSM-IV (SCID) are used for diagnostic confirmation of depression.

Affective disorders in patients with MD can only be detected by means of a clinician-administered diagnostic interview. Organic exclusion rules and other criteria are used in making the diagnosis of MD.

Schizophrenia is diagnosed based on criteria in either the American Psychiatric Association's (APA) fifth edition of the "Diagnostic and Statistical Manual of Mental Disorders" (DSM 5), or the World Health Organization's International Statistical Classification of Diseases and Related Health Problems (ICD-10). These criteria use the self-reported experiences of the person and reported abnormalities in behavior, followed by a clinical assessment by a mental health professional. Symptoms associated with schizophrenia occur along a continuum in the population and must reach a certain severity and level of impairment, before a diagnosis is made. As of 2013 there is no objective test.

In 2013, the American Psychiatric Association released the fifth edition of the DSM (DSM-5). To be diagnosed with schizophrenia, two diagnostic criteria have to be met over much of the time of a period of at least one month, with a significant impact on social or occupational functioning for at least six months. The person had to be suffering from delusions, hallucinations, or disorganized speech. A second symptom could be negative symptoms, or severely disorganized or catatonic behaviour. The definition of schizophrenia remained essentially the same as that specified by the 2000 version of DSM (DSM-IV-TR), but DSM-5 makes a number of changes.

- Subtype classifications – such as catatonic and paranoid schizophrenia – are removed. These were retained in previous revisions largely for reasons of tradition, but had subsequently proved to be of little worth.

- Catatonia is no longer so strongly associated with schizophrenia.

- In describing a person's schizophrenia, it is recommended that a better distinction be made between the current state of the condition and its historical progress, to achieve a clearer overall characterization.

- Special treatment of Schneider's first-rank symptoms is no longer recommended.

- Schizoaffective disorder is better defined to demarcate it more cleanly from schizophrenia.

- An assessment covering eight domains of psychopathology – such as whether hallucination or mania is experienced – is recommended to help clinical decision-making.

The ICD-10 criteria are typically used in European countries, while the DSM criteria are used in the United States and to varying degrees around the world, and are prevailing in research studies. The ICD-10 criteria put more emphasis on Schneiderian first-rank symptoms. In practice, agreement between the two systems is high. The current proposal for the ICD-11 criteria for schizophrenia recommends adding self-disorder as a symptom.

If signs of disturbance are present for more than a month but less than six months, the diagnosis of schizophreniform disorder is applied. Psychotic symptoms lasting less than a month may be diagnosed as brief psychotic disorder, and various conditions may be classed as psychotic disorder not otherwise specified, while schizoaffective disorder is diagnosed if symptoms of mood disorder are substantially present alongside psychotic symptoms. If the psychotic symptoms are the direct physiological result of a general medical condition or a substance, then the diagnosis is one of a psychosis secondary to that condition. Schizophrenia is not diagnosed if symptoms of pervasive developmental disorder are present unless prominent delusions or hallucinations are also present.

In those with mental health problems a number of treatments may reduce the risk of suicide. Those who are actively suicidal may be admitted to psychiatric care either voluntarily or involuntarily. Possessions that may be used to harm oneself are typically removed. Some clinicians get patients to sign suicide prevention contracts where they agree to not harm themselves if released. Evidence however does not support a significant effect from this practice. If a person is at low risk, outpatient mental health treatment may be arranged. Short-term hospitalization has not been found to be more effective than community care for improving outcomes in those with borderline personality disorder who are chronically suicidal.

There is tentative evidence that psychotherapy, specifically, dialectical behaviour therapy reduces suicidality in adolescents as well as in those with borderline personality disorder. It may also be useful in decreasing suicide attempts in adults at high risk. Evidence however has not found a decrease in completed suicides.

There is controversy around the benefit-versus-harm of antidepressants. In young persons, some antidepressants, such as SSRIs, appear to increase the risk of suicidality from 25 per 1000 to 40 per 1000. In older persons, however, they might decrease the risk. Lithium appears effective at lowering the risk in those with bipolar disorder and unipolar depression to nearly the same levels as the general population. Clozapine may decrease the thoughts of suicide in some people with schizophrenia.

The traditional method for treating patients suffering from dual diagnosis was a parallel treatment program. In this format, patients received mental health services from one clinician while addressing their substance abuse with a separate clinician. However, researchers found that parallel treatments were ineffective, suggesting a need to integrate the services addressing mental health with those addressing substance abuse.

During the mid-1980s, a number of initiatives began to combine mental health and substance abuse services in an attempt to meet this need. These programs worked to shift the method of treatment for substance abuse from a confrontational approach to a supportive one. They also introduced new methods to motivate clients and worked with them to develop long-term goals for their care. Although the studies conducted by these initiatives did not have control groups, their results were promising and became the basis for more rigorous efforts to study and develop models of integrated treatment.

Current nosological approach does not provide a framework for internal (sub-threshold symptoms) or external (comorbidity) heterogeneity of the different diagnostic categories. The prevailing "Neo-Kraepelinian" diagnostic system solely accounts for a categorical diagnosis, therefore not allowing for the possibility of dual diagnosis. There has been substantial criticism to the "Diagnostic and Statistical Manual of Mental Disorders" (DSM-IV), due to problems of diagnostic overlap, lack of clear boundaries between normality and disease, a failure to take into account findings from novel research and the lack of diagnostic stability over time.

Brain imaging (functional/structural MRI) may help direct the search for microscopic abnormalities in brain structure and function responsible for late life depression. Ultimately, imaging technologies may serve as tools for early diagnosis and subtyping of depression.

The person may have repeated thoughts about death (other than the fear of dying) or suicide (with or without a plan), or may have made a suicide attempt. The frequency and intensity of thoughts about suicide can range from believing that friends and family would be better off if one were dead, to frequent thoughts about committing suicide (generally related to wishing to stop the emotional pain), to detailed plans about how the suicide would be carried out. Those who are more severely suicidal may have made specific plans and decided upon a day and location for the suicide attempt.

Paranoid schizophrenia is an illness that typically requires lifelong treatment with neuroleptics to allow someone to have a relatively stable and normal lifestyle. In order to be successfully treated, a person with schizophrenia should seek help from family or primary care doctors, psychiatrists, psychotherapists, pharmacists, family members, case workers, psychiatric nurses, or social workers, provided he or she is not unable to do so, due to many people with schizophrenia having the inability to accept their condition. Non-compliance with neuroleptics may also occur if the patient considers the side effects (such as extrapyramidal symptoms) to be more debilitating than the condition itself. The main options that are offered for the treatment of paranoid schizophrenia are the following: neuroleptics, psychotherapy, hospitalization, electroconvulsive therapy, and vocational skills training.

There are many different types of disorders that have similar symptoms to paranoid schizophrenia. There are tests that psychiatrists perform to achieve a correct diagnosis. They include "psychiatric evaluation, in which the doctor or psychiatrist will ask a series of questions about the patient's symptoms, psychiatric history, and family history of mental health problems; medical history and exam, in which the doctor will ask about one's personal and family health history and will also perform a complete physical examination to check for medical issues that could be causing or contributing to the problem; laboratory tests in which the doctor will order simple blood and urine tests can rule out other medical causes of symptoms".

There are side effects associated with antipsychotic medication. Neuroleptics can cause high blood pressure and high cholesterol. Many people who take them exhibit weight gain and have a higher risk of developing diabetes.

Depressed mood may not require professional treatment, and may be a normal temporary reaction to life events, a symptom of some medical condition, or a side effect of some drugs or medical treatments. A prolonged depressed mood, especially in combination with other symptoms, may lead to a diagnosis of a psychiatric or medical condition which may benefit from treatment. Different sub-divisions of depression have different treatment approaches.

In the United States, it has been estimated that two thirds of people with depression do not actively seek treatment. The World Health Organisation (WHO) has predicted that by 2030, depression will account for the highest level of disability accorded any physical or mental disorder in the world (WHO, 2008).

The UK National Institute for Health and Care Excellence (NICE) 2009 guidelines indicate that antidepressants should not be routinely used for the initial treatment of mild depression, because the risk-benefit ratio is poor. A recent meta-analysis also indicated that most antidepressants, besides fluoxetine, do not seem to offer a clear advantage for children and adolescents in the acute treatment of major depressive disorder.

In the opinion of Allen Frances, chair of the DSM-IV task force, the DSM-5's somatic symptom disorder brings with it a risk of mislabeling a sizable proportion of the population as mentally ill. “Millions of people could be mislabeled, with the burden falling disproportionately on women, because they are more likely to be casually dismissed as ‘catastrophizers’ when presenting with physical symptoms.”

According to the Mayo Clinic, it is best to start receiving treatment for paranoid schizophrenia as early as possible and to maintain the treatment throughout life. Continuing treatment will help keep the serious symptoms under control and allow the person to lead a more fulfilling life. This illness is typically unpreventable.

It has a strong hereditary component with a first degree parent or sibling. There is some possibility that there are environmental influences including "prenatal exposure to a viral infection, low oxygen levels during birth (from prolonged labor or premature birth), exposure to a virus during infancy, early parental loss or separation, and verbal, physical or sexual abuse in childhood". Eliminating any of these factors could help reduce an individual's future risk of developing paranoid schizophrenia.

Somatic symptom disorder has been a controversial diagnosis, since it was historically based primarily on negative criteria - that is, the absence of a medical explanation for the presenting physical complaints. Consequently, any person suffering from a poorly understood illness can potentially fulfill the criteria for this psychiatric diagnosis, even if they exhibit no psychiatric symptoms in the conventional sense. In 2013-4, there were several widely publicized cases of individuals being involuntarily admitted to psychiatric wards on the basis of this diagnosis alone. This has raised concerns about the consequences of potential misuse of this diagnostic category.

As it has already been mentioned, patients with organic personality disorder show a wide variety of sudden behavioural changes and dysfunctions. There are not a lot of information about the treatment of this mental health disorder. The pharmacological approach is the most common therapy among patients with organic personality disorder. However, the choice of drug therapy relies on the seriousness of patient's situation and what symptoms are shown. The choice and administration of specific drugs contribute to the reduction of symptoms of organic personality disorder. For this reason, it is crucial for patients' treatment to be assessed by clinical psychologists and psychiatrists before the administration of drug.

Additionally, the dysfunctions in expression of behaviour of patients with organic personality disorder and the development of symptom of irritability, which are caused by aggressive and self-injurious behaviours, can be dealt with the administration of carbamazepine. Moreover, the symptoms of this disorder can be decreased by the administration of valproic acid. Also, emotional irritability and signs of depression can be dealt with the use of nortriptyline and low-dose thioridazine. Except from the symptom of irritability, patients express aggressive behaviours. At the onset of drug therapy for effective treatment of anger and aggression, the drug of carbamazepine, phenobarbital, benztropine and haloperidol can be administrated in order to reduce the symptoms of patients with organic personality disorder. In addition, the use of propranolol may decrease the frequent behaviours of rage attacks.

Finally, it is important for patients to take part in psychotherapy sessions during the period of drug therapy. In this way, there is prevention and patients can be protected by negative effects of drugs on their organism and their behaviour. Furthermore, the clinicians can provide useful and helpful support to patients during these psychotherapy sessions. Thus, the combination of drug therapy with psychotherapy can lead to the reduction of symptoms of this disorder and the improvement of patients' situation.

From the :

F33 Recurrent depressive disorder

- G1.There has been at least one previous episode, mild (F32.0), moderate (F32.1), or severe (F32.2 or F32.3), lasting a minimum of 2 weeks and separated from the current episode by at least 2 months free from any significant mood symptoms.

- G2. At no time in the past has there been an episode meeting the criteria or hypomanic or manic episode (F30.-).

- G3. Most commonly used exclusion criteria: the episode is not attributable to psychoactive substance use (F1) or any organic mental disorder, in the sense of F0. It is recommended to specify the predominant type of previous episodes (mild, moderate, severe, uncertain).

F33.0 Recurrent depressive disorder, current episode mild

- A. The general criteria for recurrent depressive disorder (F33) are met.

- B. The current episode meets the criteria for depressive episode, mild severity (F32.0).

- A fifth character may be used to specify the presence of the somatic syndrome, as defined in F32, in the current episode:

- F33.00 without somatic syndrome

- F33.01 with somatic syndrome

F33.1 Recurrent depressive disorder, current episode moderate

- A. The general criteria for recurrent depressive disorders (F33) are met.

- B. The current episode meets the criteria for depressive episode, moderate severity (F32.1).

- A fifth character may be used to specify the presence of the somatic syndrome, as defined in F32, in the current episode:

F33.10 without somatic syndrome

F33.11 with somatic syndrome

F33.2 Recurrent depressive disorder, current episode severe without psychotic symptoms

- A. The general criteria for recurrent depressive disorders (F33) are met.

- B. The current episode meets the criteria for severe depressive episode without psychotic symptoms (F32.2).

F33.3 Recurrent depressive disorder, current episode severe with psychotic symptoms

- A. The general criteria for recurrent depressive disorders (F33) are met.

- B. The current episode meets the criteria for severe depressive episode with psychotic symptoms (F32.3). A fifth character may be used to specify whether the psychotic symptoms are congruent or incongruent with the mood:

F33.30 with mood congruent psychotic symptoms

F33.31 with mood incongruent psychotic symptoms

F33.4 Recurrent depressive disorder, currently in remission

- A. The general criteria for recurrent depressive disorder (F33) have been met in the past.

- B. The current state does not meet the criteria for a depressive episode (F32.-) of any severity, or for any other disorder in F3 (the patient may receive treatment to reduce the risk of further episodes).

F33.8 Other recurrent depressive disorders

F33.9 Recurrent depressive disorder, unspecified

In most instances, stating categorically that an individual is malingering requires an explicit admission by that individual. Legally the term may be considered prejudicial and excluded on that basis. No current research exists regarding the frequency, behaviour or detection of successful malingerers. No neuropsychological inventories exist that can be used to conclusively determine if a patient is malingering, or to exclude a determination of malingering. Genuine neurological and psychiatric conditions may return false positives. Testing inventories cannot distinguish between exaggeration and fabrication. Psychological inventories rely on naivety. Criminally, an assessment may lead to punishment enhancement, and medically, to denial of future treatment. The DSM-V criteria faces scrutiny for providing poor guidelines. As such physicians ultimately rely on their intuition and gut feeling for any assessment, which is subject to prejudice and cognitive dissonance, and which has been shown to be unreliable in synthetic tests.

Malingering presumes an exhaustive diagnostic procedure has been performed. Exhaustive diagnostics are neither practical nor economically viable or judged to be in the best interests of the patient's health. Radiological and invasive exploratory procedures can be necessary for an accurate diagnosis yet pose a health risk to the patient. Radiographic diagnostics expose the patient to radiation and surgical diagnostic procedures can carry a high risk of complications and mortality, such as a lumbar puncture, the only reliable diagnostic procedure for diagnosing rare terminal forms of parasitization, which the CDC reports as only being diagnosed "post mortem" 75% of the time. A physician invariably faces limitations in the realms of resources, time and liability. Because an assessment, formal or informal, of malingering ceases the medical process, it may seem an attractive option for the physician and help them to cope with cognitive dissonance over their failure to effectively diagnose and treat a patient within constraints.

Patients with unresolved illness may be adversarial towards physicians, attempting to game the triage system in order to receive specialist care. Such cases fit the criteria for malingering, yet the patient is still in need of medical care.

For example, in a gatekeeper system, primary care physicians may restrict the availability of HIV testing to only patients who report high risk activity. A patient may then falsely report sexual and/or drug history and/or symptoms in order to elevate priority which can then go on to serve as diagnostically relevant history for an inaccurate path of further diagnosis.

Medical practitioners often believe that they can detect deception. In two studies, experienced medical practitioners including psychiatrists failed to perform better than chance when asked to detect lying and simulated patients. In 12 other studies, detection rates of simulated patients ranged between 0 and 25%. It's impossible to detect malingering from a clinical perspective.