The rate of BPD varies among institutions, which may reflect neonatal risk factors, care practices (e.g., target levels for acceptable oxygen saturation), and differences in the clinical definitions of BPD.

There is evidence to show that steroids given to babies less than 8 days old can prevent bronchopulmonary dysplasia. However, the risks of treatment may outweigh the benefits.

It is unclear if starting steroids more than 7 days after birth is harmful or beneficial. It is thus recommended that they only be used in those who cannot be taken off of a ventilator.

Giving the mother glucocorticoids speeds the production of surfactant. For very premature deliveries, a glucocorticoid is given without testing the fetal lung maturity. The American College of Obstetricians and Gynecologists (ACOG), Royal College of Medicine, and other major organizations have recommended antenatal glucocorticoid treatment for women at risk for preterm delivery prior to 34 weeks of gestation. Multiple courses of glucocorticoid administration, compared with a single course, does not seem to increase or decrease the risk of death or neurodevelopmental disorders of the child.

In pregnancies of greater than 30 weeks, the fetal lung maturity may be tested by sampling the amount of surfactant in the amniotic fluid by amniocentesis, wherein a needle is inserted through the mother's abdomen and uterus. Several tests are available that correlate with the production of surfactant. These include the lecithin-sphingomyelin ratio ("L/S ratio"), the presence of phosphatidylglycerol (PG), and more recently, the surfactant/albumin (S/A) ratio. For the L/S ratio, if the result is less than 2:1, the fetal lungs may be surfactant deficient. The presence of PG usually indicates fetal lung maturity. For the S/A ratio, the result is given as mg of surfactant per gm of protein. An S/A ratio 55 indicates mature surfactant production(correlates with an L/S ratio of 2.2 or greater).

Oxygen is given with a small amount of continuous positive airway pressure ("CPAP"), and intravenous fluids are administered to stabilize the blood sugar, blood salts, and blood pressure. If the baby's condition worsens, an endotracheal tube (breathing tube) is inserted into the trachea and intermittent breaths are given by a mechanical device. An exogenous preparation of surfactant, either synthetic or extracted from animal lungs, is given through the breathing tube into the lungs. Some of the most commonly used surfactants are Survanta or its generic form Beraksurf, derived from cow lungs, which can decrease the risk of death in hospitalized very-low-birth-weight infants by 30%. Such small premature infants may remain ventilated for months. A study shows that an aerosol of a perfluorocarbon such as perfluoromethyldecalin can reduce inflammation in swine model of IRDS. Chronic lung disease including bronchopulmonary dysplasia are common in severe RDS. The etiology of BPD is problematic and may be due to oxygen, overventilation or underventilation. The mortality rate for babies greater than 27 weeks gestation is less than 20%

Extracorporeal membrane oxygenation (ECMO) is a potential treatment, providing oxygenation through an apparatus that imitates the gas exchange process of the lungs. However, newborns cannot be placed on ECMO if they are under 4.5 pounds (2 kg), because they have extremely small vessels for cannulation, thus hindering adequate flow because of limitations from cannula size and subsequent higher resistance to blood flow (compare with vascular resistance). Furthermore, in infants aged less than 34 weeks of gestation several physiologic systems are not well-developed, specially the cerebral vasculature and germinal matrix, resulting in high sensitivity to slight changes in pH, PaO, and intracranial pressure. Subsequently, preterm infants are at unacceptably high risk for intraventricular hemorrhage (IVH) if administered ECMO at a gestational age less than 32 weeks.

- The INSURE Method

Henrik Verder is the inventor and pioneer of the INSURE method, a very effective approach to managing preterm neonates with respiratory distress. The method itself has been shown, through meta-analysis; to successfully decrease the use of mechanical ventilation and lower the incidence of bronchopulmonary dysplasia (BPD). Since its conception in 1989 the INSURE method has been academically cited in more than 500 papers. The first randomised study about the INSURE method was published in 1994 and a second randomised study in infants less than 30 weeks gestation was published by the group in 1999. In the last 15 years Henrik has worked with lung maturity diagnostics on gastric aspirates obtained at birth. By combining this diagnostic method with INSURE, Henrik has worked to further improve the clinical outcome of RDS. The lung maturity tests used have been the microbubble test, lamellar body counts (LBC) and measurements of lecithin-sphingomyelin ratio (L/S) with chemometrics, which involved a collaboration with Agnar Höskuldsson.

Wilson–Mikity syndrome, also known as pulmonary dysmaturity syndrome, is a rare lung condition that affects low birth weight babies.

It is closely related to bronchopulmonary dysplasia, differing mainly in the lack of prior ventilatory support. All the initial patients described with Wilson–Mikity syndrome were very low birth weight infants that had no history of mechanical ventilation and yet developed a syndrome that clinically resembled BPD. Upon the death of some of these infants, autopsies showed histologic changes also similar to those seen in BPD.

It was characterized by Miriam G. Wilson and Victor G. Mikity in 1960.

Obstetric ultrasound has become useful in the assessment of the cervix in women at risk for premature delivery. A short cervix preterm is undesirable: A cervical length of less than 25 mm at or before 24 weeks of gestational age is the most common definition of cervical incompetence.

Fetal fibronectin (fFN) has become an important biomarker—the presence of this glycoprotein in the cervical or vaginal secretions indicates that the border between the chorion and deciduas has been disrupted. A positive test indicates an increased risk of preterm birth, and a negative test has a high predictive value. It has been shown that only 1% of women in questionable cases of preterm labor delivered within the next week when the test was negative.

There is as yet no universally accepted diagnostic protocol for reactive attachment disorder. Often a range of measures is used in research and diagnosis. Recognized assessment methods of attachment styles, difficulties or disorders include the Strange Situation Procedure (devised by developmental psychologist Mary Ainsworth), the separation and reunion procedure and the Preschool Assessment of Attachment, the Observational Record of the Caregiving Environment, the Attachment Q-sort and a variety of narrative techniques using stem stories, puppets or pictures. For older children, actual interviews such as the Child Attachment Interview and the Autobiographical Emotional Events Dialogue can be used. Caregivers may also be assessed using procedures such as the Working Model of the Child Interview.

More recent research also uses the Disturbances of Attachment Interview (DAI) developed by Smyke and Zeanah (1999). The DAI is a semi-structured interview designed to be administered by clinicians to caregivers. It covers 12 items, namely "having a discriminated, preferred adult", "seeking comfort when distressed", "responding to comfort when offered", "social and emotional reciprocity", "emotional regulation", "checking back after venturing away from the care giver", "reticence with unfamiliar adults", "willingness to go off with relative strangers", "self-endangering behavior", "excessive clinging", "vigilance/hypercompliance" and "role reversal". This method is designed to pick up not only RAD but also the proposed new alternative categories of disorders of attachment.

RAD is one of the least researched and most poorly understood disorders in the DSM. There is little systematic epidemiologic information on RAD, its course is not well established and it appears difficult to diagnose accurately. There is a lack of clarity about the presentation of attachment disorders over the age of five years and difficulty in distinguishing between aspects of attachment disorders, disorganized attachment or the consequences of maltreatment.

According to the American Academy of Child and Adolescent Psychiatry (AACAP), children who exhibit signs of reactive attachment disorder need a comprehensive psychiatric assessment and individualized treatment plan. The signs or symptoms of RAD may also be found in other psychiatric disorders and AACAP advises against giving a child this label or diagnosis without a comprehensive evaluation. Their practice parameter states that the assessment of reactive attachment disorder requires evidence directly obtained from serial observations of the child interacting with his or her primary caregivers and history (as available) of the child’s patterns of attachment behavior with these caregivers. It also requires observations of the child’s behavior with unfamiliar adults and a comprehensive history of the child’s early caregiving environment including, for example, pediatricians, teachers, or caseworkers. In the US, initial evaluations may be conducted by psychologists, psychiatrists, Licensed Marriage and Family Therapists, Licensed Professional Counselors, specialist Licensed Clinical Social Workers or psychiatric nurses.

In the UK, the British Association for Adoption and Fostering (BAAF) advise that only a psychiatrist can diagnose an attachment disorder and that any assessment must include a comprehensive evaluation of the child’s individual and family history.

According to the AACAP Practice Parameter (2005) the question of whether attachment disorders can reliably be diagnosed in older children and adults has not been resolved. Attachment behaviors used for the diagnosis of RAD change markedly with development and defining analogous behaviors in older children is difficult. There are no substantially validated measures of attachment in middle childhood or early adolescence. Assessments of RAD past school age may not be possible at all as by this time children have developed along individual lines to such an extent that early attachment experiences are only one factor among many that determine emotion and behavior.

The utility of PTSD derived psychotherapies for assisting children with C-PTSD is uncertain. This area of diagnosis and treatment calls for caution in use of the category C-PTSD. Ford and van der Kolk have suggested that C-PTSD may not be as useful a category for diagnosis and treatment of children as a proposed category of developmental trauma disorder (DTD). For DTD to be diagnosed it requires a

'history of exposure to early life developmentally adverse interpersonal trauma such as sexual abuse, physical abuse, violence, traumatic losses of other significant disruption or betrayal of the child's relationships with primary caregivers, which has been postulated as an etiological basis for complex traumatic stress disorders. Diagnosis, treatment planning and outcome are always relational.'

Since C-PTSD or DTD in children is often caused by chronic maltreatment, neglect or abuse in a care-giving relationship the first element of the biopsychosocial system to address is that relationship. This invariably involves some sort of child protection agency. This both widens the range of support that can be given to the child but also the complexity of the situation, since the agency's statutory legal obligations may then need to be enforced.

A number of practical, therapeutic and ethical principles for assessment and intervention have been developed and explored in the field:

- Identifying and addressing threats to the child's or family's safety and stability are the first priority.

- A relational bridge must be developed to engage, retain and maximize the benefit for the child and caregiver.

- Diagnosis, treatment planning and outcome monitoring are always relational (and) strengths based.

- All phases of treatment should aim to enhance self-regulation competencies.

- Determining with whom, when and how to address traumatic memories.

- Preventing and managing relational discontinuities and psychosocial crises.

In "How Everyone Became Depressed: The Rise and Fall of the Nervous Breakdown" (2013), Edward Shorter, a professor of psychiatry and the history of medicine, argues for a return to the old-fashioned concept of nervous illness:

The terms "nervous breakdown" and "mental breakdown" have not been formally defined through a medical diagnostic system such as the DSM-5 or ICD-10, and are nearly absent from current scientific literature regarding mental illness. Although "nervous breakdown" is not rigorously defined, surveys of laypersons suggest that the term refers to a specific acute time-limited reactive disorder, involving symptoms such as anxiety or depression, usually precipitated by external stressors. Many health experts today refer to a nervous breakdown as a "modern mental health crisis."

Specific cases are sometimes described as a "breakdown" only after the emotional and physical demands on a person's life are so great as to prevent him or her from performing activities of daily living or, less strictly, only when those demands prevent him/her from performing his/her familial or occupational duties.

Nervous breakdowns are often caused by serious ongoing mental health disorders.

Diagnosis of cyclothymia is difficult for a number of reasons. The depressive-dysthymic episode of cyclothymia is also a diagnostic feature of many disorders, including adjustment disorders, personality disorders, psychotic disorders, and other mood disorders. Since depression can be triggered or exacerbated by life events and circumstances, the diagnosing clinician must determine when it is an acceptable response and when it is pathological.

Symptoms described in the hypomanic episode are also commonly associated with ADHD, such as increased energy, distractibility and impulsive or risk-seeking behavior. This is of particular concern in child psychiatry because symptoms, especially hyperactivity, may be counted twice toward both disorders or may inflate the prevalence of ADHD.

While childhood ADHD often presents with hyperactivity, adult ADHD often does not. The unstable lifestyle often found both in people with ADHD and in those with cyclothymia can cause problems for differential diagnosis. Important distinguishing factors include that ADHD is characterized mainly by problems with concentration and memory, while cyclothymia mainly by periods of elevated self-confidence and elation.

Whether subtypes of bipolar disorder, such as cyclothymia truly represent separate disorders or are part of a unique bipolar spectrum is still debated in research. Cyclothymia is typically not described in research studies or diagnosed in clinical settings, making it less recognizable and less understood by professionals. This absence of cyclothymia in research and clinical settings suggests that cyclothymia is either being diagnosed as another mood disorder or as a non-affective psychiatric disorder or not coming to scientific or clinical attention due to a lack of diagnostic clarity or because the nature of cyclothymia is still highly contested. Additionally, the current diagnostic criterion for cyclothymia emphasizes that symptoms are persistent, which suggests that they are enduring traits rather than a psychological state, thus, it has been argued that it should be diagnosed as a personality disorder. Since the symptoms tend to overlap with personality disorders, the validity and distinction between these two diagnostic categories has been debated.

Lastly, the tendency of cyclothymia to be comorbid with other mental disorders makes diagnosis difficult. These issues prevent consensus on the definition of cyclothymia and its relationship with other mental disorders among researchers and clinicians. This lack of consensus on an operational definition and symptom presentation is especially pronounced with children and adolescents because the diagnostic criteria have not been adequately adapted to take into account their developmental level. However, there has been a shift from categorical models of bipolar related disorders toward a dimensional model, which is intended to address some of these issues.

This disorder is common in the relatives of patients with bipolar disorder, and some individuals with cyclothymia eventually develop bipolar disorder themselves. It may persist throughout adult life, cease temporarily or permanently, or develop into more severe mood swings, meeting the criteria for bipolar disorder or recurrent depressive disorder in some cases.

Herman believes recovery from C-PTSD occurs in three stages:

1. establishing safety,

2. remembrance and mourning for what was lost,

3. reconnecting with community and more broadly, society.

Herman believes recovery can only occur within a healing relationship and only if the survivor is empowered by that relationship. This healing relationship need not be romantic or sexual in the colloquial sense of "relationship", however, and can also include relationships with friends, co-workers, one's relatives or children, and the therapeutic relationship.

Complex trauma means complex reactions and this leads to complex treatments. Hence, treatment for C-PTSD requires a multi-modal approach. It has been suggested that treatment for C-PTSD should differ from treatment for PTSD by focusing on problems that cause more functional impairment than the PTSD symptoms. These problems include emotional dysregulation, dissociation, and interpersonal problems. Six suggested core components of complex trauma treatment include:

1. Safety

2. Self-regulation

3. Self-reflective information processing

4. Traumatic experiences integration

5. Relational engagement

6. Positive affect enhancement

Multiple treatments have been suggested for C-PTSD. Among these treatments are experiential and emotionally focused therapy, internal family systems therapy, sensorimotor psychotherapy, eye movement desensitization and reprocessing therapy (EMDR), dialectical behavior therapy (DBT), cognitive behavioral therapy, psychodynamic therapy, family systems therapy and group therapy.

Hypersexuality may negatively impact an individual. The concept of hypersexuality as an addiction was started in the 1970s by former members of Alcoholics Anonymous who felt they experienced a similar lack of control and compulsivity with sexual behaviors as with alcohol. Multiple 12-step style self-help groups now exist for people who identify as sex addicts, including Sex Addicts Anonymous, Sexaholics Anonymous, Sex and Love Addicts Anonymous, and Sexual Compulsives Anonymous. Some hypersexuals may treat their condition with the usage of medication or any foods considered to be anaphrodisiacs. Other hypersexuals may choose a route of consultation, such as psychotherapy, self-help groups or counselling.

Perhaps due to their perceived rarity, the dissociative disorders (including DID) were not initially included in the Structured Clinical Interview for DSM-IV (SCID), which is designed to make psychiatric diagnoses more rigorous and reliable. Instead, shortly after the publication of the initial SCID a freestanding protocol for dissociative disorders (SCID-D) was published. This interview takes about 30 to 90 minutes depending on the subject's experiences. An alternative diagnostic instrument, the Dissociative Disorders Interview Schedule, also exists but the SCID-D is generally considered superior. The Dissociative Disorders Interview Schedule (DDIS) is a highly structured interview that discriminates among various DSM-IV diagnoses. The DDIS can usually be administered in 30–45 minutes.

Other questionnaires include the Dissociative Experiences Scale (DES), Perceptual Alterations Scale, Questionnaire on Experiences of Dissociation, Dissociation Questionnaire, and the Mini-SCIDD. All are strongly intercorrelated and except the Mini-SCIDD, all incorporate absorption, a normal part of personality involving narrowing or broadening of attention. The DES is a simple, quick, and validated questionnaire that has been widely used to screen for dissociative symptoms, with variations for children and adolescents. Tests such as the DES provide a quick method of screening subjects so that the more time-consuming structured clinical interview can be used in the group with high DES scores. Depending on where the cutoff is set, people who would subsequently be diagnosed can be missed. An early recommended cutoff was 15-20. The reliability of the DES in non-clinical samples has been questioned.

The use of lithium and quetiapine (Seroquel) have both shown to be particularly valuable, though several other medications of the anticonvulsants and atypical antipsychotics classes may also be helpful.

- Lithium – Lithium has been shown to help stabilize the mood of patients suffering from cyclothymia and as well as bipolar disorders. It also aids in the prevention of acute suicidal and manic episodes. Dosage must be carefully monitored as lithium has a plethora of side effects.

- Atypical antipsychotics – (e.g., quetiapine (Seroquel), also olanzapine (Zyprexa), and risperidone (Risperdal).

- Anticonvulsants – (e.g., valproic acid, lamotrigine (Lamictal), and valproate semisodium (Depakote)).

- Electroconvulsive therapy – Through a systematic review done by Versiani, Cheriaux, and Landeira-Fernandez, it was determined that the efficacy and safety of ECT in patients with bipolar disorder had been poorly investigated and the evidence had methodological limitations.

Diagnosis of borderline personality disorder is based on a clinical assessment by a mental health professional. The best method is to present the criteria of the disorder to a person and to ask them if they feel that these characteristics accurately describe them. Actively involving people with BPD in determining their diagnosis can help them become more willing to accept it. Although some clinicians prefer not to tell people with BPD what their diagnosis is, either from concern about the stigma attached to this condition or because BPD used to be considered untreatable, it is usually helpful for the person with BPD to know their diagnosis. This helps them know that others have had similar experiences and can point them toward effective treatments.

In general, the psychological evaluation includes asking the patient about the beginning and severity of symptoms, as well as other questions about how symptoms impact the patient's quality of life. Issues of particular note are suicidal ideations, experiences with self-harm, and thoughts about harming others. Diagnosis is based both on the person's report of their symptoms and on the clinician's own observations. Additional tests for BPD can include a physical exam and laboratory tests to rule out other possible triggers for symptoms, such as thyroid conditions or substance abuse. The ICD-10 manual refers to the disorder as "emotionally unstable personality disorder" and has similar diagnostic criteria. In the DSM-5, the name of the disorder remains the same as in the previous editions.

The fourth, revised edition of the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders (DSM-IV-TR) diagnoses DID according to the diagnostic criteria found in section 300.14 (dissociative disorders). It has also been found difficult to diagnose the disorder in the first place, due to there not being a universal agreement of the definition of dissociation. The criteria require that an adult be recurrently controlled by two or more discrete identities or personality states, accompanied by memory lapses for important information that is not caused by alcohol, drugs or medications and other medical conditions such as complex partial seizures. While otherwise similar, the diagnostic criteria for children also specifies symptoms must not be confused with imaginative play. Diagnosis is normally performed by a clinically trained mental health professional such as a psychiatrist or psychologist through clinical evaluation, interviews with family and friends, and consideration of other ancillary material. Specially designed interviews (such as the SCID-D) and personality assessment tools may be used in the evaluation as well. Since most of the symptoms depend on self-report and are not concrete and observable, there is a degree of subjectivity in making the diagnosis. People are often disinclined to seek treatment, especially since their symptoms may not be taken seriously; thus dissociative disorders have been referred to as "diseases of hiddenness".

The diagnosis has been criticized by supporters of therapy as a cause or the sociocognitive hypothesis as they believe it is a culture-bound and often health care induced condition. The social cues involved in diagnosis may be instrumental in shaping patient behavior or attribution, such that symptoms within one context may be linked to DID, while in another time or place the diagnosis could have been something other than DID. Other researchers disagree and argue that the existence of the condition and its inclusion in the DSM is supported by multiple lines of reliable evidence, with diagnostic criteria allowing it to be clearly discriminated from conditions it is often mistaken for (schizophrenia, borderline personality disorder, and seizure disorder). That a large proportion of cases are diagnosed by specific health care providers, and that symptoms have been created in nonclinical research subjects given appropriate cueing has been suggested as evidence that a small number of clinicians who specialize in DID are responsible for the creation of alters through therapy.

There is a significant difference between the number of those who would benefit from treatment and the number of those who are treated. The so-called "treatment gap" is a function of the disinclination of the afflicted to submit for treatment, an underdiagnosing of the disorder by healthcare providers, and the limited availability and access to state-of-the-art treatments. Nonetheless, individuals with BPD accounted for about 20 percent of psychiatric hospitalizations in one survey. The majority of individuals with BPD who are in treatment continue to use outpatient treatment in a sustained manner for several years, but the number using the more restrictive and costly forms of treatment, such as inpatient admission, declines with time.

Experience of services varies. Assessing suicide risk can be a challenge for clinicians, and patients themselves tend to underestimate the lethality of self-injurious behaviors. People with BPD typically have a chronically elevated risk of suicide much above that of the general population and a history of multiple attempts when in crisis. Approximately half the individuals who commit suicide meet criteria for a personality disorder. Borderline personality disorder remains the most commonly associated personality disorder with suicide.

After the death of a patient in 2014 NHS England was criticised by a coroner for the lack of commissioned services to support such patients. Evidence was given that 45% of mentally disordered females had BPD and there was no provision or priority for therapeutic psychological services. There were only 60 specialised inpatient beds in England – all in the North East or London.

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."

Data from the 2001–02 National Epidemiologic Survey on Alcohol and Related Conditions indicates a prevalence rate of 2.36% in the American general population. It appears to occur with equal frequency in males and females. In one study, it was seen in 14.7% of psychiatric outpatients.

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.

, a proposal to add "Sexual Addiction" to the Diagnostic and Statistical Manual of Mental Disorders (DSM) system has failed to get support of the American Psychiatric Association (APA). The DSM does include an entry called Sexual Disorder Not Otherwise Specified (Sexual Disorder NOS) to apply to, among other conditions, "distress about a pattern of repeated sexual relationships involving a succession of lovers who are experienced by the individual only as things to be used".

The International Statistical Classification of Diseases and Related Health Problems (ICD-10) of the World Health Organization (WHO), includes two relevant entries. One is "Excessive Sexual Drive" (coded F52.7), which is divided into satyriasis for males and nymphomania for females. The other is "Excessive Masturbation" or "Onanism (excessive)" (coded F98.8).

Some authors have questioned whether it makes sense to discuss hypersexuality at all, arguing that labeling sexual urges "extreme" merely stigmatizes people who do not conform to the norms of their culture or peer group.

Being a personality disorder, which are usually chronic and long-lasting mental conditions, avoidant personality disorder is not expected to improve with time without treatment. It is a poorly studied personality disorder and in light of prevalence rates, societal costs, and the current state of research, AvPD qualifies as a neglected disorder.