Little is known about prognosis of untreated DID. It rarely, if ever, goes away without treatment, but symptoms may resolve from time to time or wax and wane spontaneously. Patients with mainly dissociative and posttraumatic symptoms face a better prognosis than those with comorbid disorders or those still in contact with abusers, and the latter groups often face lengthier and more difficult treatment. Suicidal ideation, failed suicide attempts, and self-harm also occur. Duration of treatment can vary depending on patient goals, which can extend from elimination of all alters to merely reducing inter-alter amnesia, but generally takes years.

According to Professor Emily Simonoff of the Institute of Psychiatry, Psychology and Neuroscience, "childhood hyperactivity and conduct disorder showed equally strong prediction of antisocial personality disorder (ASPD) and criminality in early and mid-adult life. Lower IQ and reading problems were most prominent in their relationships with childhood and adolescent antisocial behaviour."

DID is rarely diagnosed in children, despite the average age of appearance of the first alter being three years. This fact is cited as a reason to doubt the validity of DID, and proponents of both etiologies believe that the discovery of DID in a child that had never undergone treatment would critically undermine the SCM. Conversely, if children are found to only develop DID after undergoing treatment it would challenge the traumagenic model. , approximately 250 cases of DID in children have been identified, though the data does not offer unequivocal support for either theory. While children have been diagnosed with DID before therapy, several were presented to clinicians by parents who were themselves diagnosed with DID; others were influenced by the appearance of DID in popular culture or due to a diagnosis of psychosis due to hearing voices—a symptom also found in DID. No studies have looked for children with DID in the general population, and the single study that attempted to look for children with DID not already in therapy did so by examining siblings of those already in therapy for DID. An analysis of diagnosis of children reported in scientific publications, 44 case studies of single patients were found to be evenly distributed (i.e., each case study was reported by a different author) but in articles regarding groups of patients, four researchers were responsible for the majority of the reports.

The initial theoretical description of DID was that dissociative symptoms were a means of coping with extreme stress (particularly childhood sexual and physical abuse), but this belief has been challenged by the data of multiple research studies. Proponents of the traumagenic hypothesis claim the high correlation of child sexual and physical abuse reported by adults with DID corroborates the link between trauma and DID. However, the DID-maltreatment link has been questioned for several reasons. The studies reporting the links often rely on self-report rather than independent corroborations, and these results may be worsened by selection and referral bias. Most studies of trauma and dissociation are cross-sectional rather than longitudinal, which means researchers can not attribute causation, and studies avoiding recall bias have failed to corroborate such a causal link. In addition, studies rarely control for the many disorders comorbid with DID, or family maladjustment (which is itself highly correlated with DID). The popular association of DID with childhood abuse is relatively recent, occurring only after the publication of "Sybil" in 1973. Most previous examples of "multiples" such as Chris Costner Sizemore, whose life was depicted in the book and film "The Three Faces of Eve", disclosed no history of child abuse.

Personality disorders are seen to be caused by a combination and interaction of genetic and environmental influences. Genetically, it is the intrinsic temperamental tendencies as determined by their genetically influenced physiology, and environmentally, it is the social and cultural experiences of a person in childhood and adolescence encompassing their family dynamics, peer influences, and social values.

Spoiling in early childhood tends to create characteristic reactions that persist, fixed, into later life. These can cause significant social problems. Spoiled children may have difficulty coping with situations such as teachers scolding them or refusing to grant extensions on homework assignments, playmates refusing to allow them to play with their toys and playmates refusing playdates with them, a loss in friends, failure in employment, and failure with personal relationships. As adults, spoiled children may experience problems with anger management, professionalism, and personal relationships; a link with adult psychopathy has been observed.

Treatment by a physician involves assessing parental competence, and whether the parents set limits correctly and consistently. Physicians should rule out dysfunction in the family, referring dysfunctional families for family therapy and dysfunctional parents for parenting skills training, and counsel parents in methods for modifying their child's behavior.

Studies suggest that the prevalence of paraphrenia in the elderly population is around 2-4%.

A self-disorder, also called ipseity disturbance, is a psychological phenomenon of disruption or diminishing of a person's sense of minimal (or basic) self. The sense of minimal self refers to the very basic sense of having experiences that are one's own; it has no properties, unlike the more extended sense of self, the narrative self, which is characterized by the person's reflections on themselves as a person, things they like, their identity, and other aspects that are the result of reflection on one's self. Disturbances in the sense of minimal self, as measured by the Examination of Anomalous Self-Experience (EASE), aggregate in the schizophrenia spectrum disorders, to include schizotypal personality disorder, and distinguish them from other conditions such as psychotic bipolar disorder and borderline personality disorder.

While paraphrenia can occur in both men and women, it is more common in women, even after the difference has been adjusted for life expectancies. The ratio of women with paraphrenia to men with paraphrenia is anywhere from 3:1 to 45:2

The minimal self has been likened to a "flame that enlightens its surroundings and thereby itself." Unlike the extended self, which is composed of properties such as the person's identity, the person's narrative, and other aspects that can be gleaned from reflection, the minimal self has no properties, but refers to the "mine-ness" "given-ness" of experience, that the experiences are that of the person having them in that person's stream of consciousness. These experiences that are part of the minimal self are normally "tacit" and implied, requiring no reflection on the part of the person experiencing to know that the experience is theirs. The minimal self cannot be further elaborated and normally one cannot grasp it upon reflection. The minimal self goes hand-in-hand with immersion in the shared social world, such that "[t]he world is always pregiven, ie, tacitly grasped as a self-evident background of all experiencing and meaning." This is the self-world structure.

De Warren gives an example of the minimal self combined with immersion in the shared social world: "When looking at this tree in my backyard, my consciousness is directed toward the tree and not toward my own act of perception. I am, however, aware of myself as perceiving this tree, yet this self-awareness (or self-consciousness) is not itself thematic." The focus is normally on the tree itself, not on the person's own act of seeing the tree: to know that one is seeing the tree does not require an act of reflection.

Risk factors (constructs which increase the likelihood or intensity of homesickness) and protective factors (constructs that decrease the likelihood or intensity of homesickness) vary by population. For example, a seafarers on board, the environmental stressors associated with a hospital, a military boot camp or a foreign country may exacerbate homesickness and complicate treatment. Generally speaking, however, risk and protective factors transcend age and environment.

The risk factors for homesickness fall into five categories: experience, personality, family, attitude and environment. More is known about some of these factors in adults—especially personality factors—because more homesickness research has been performed with older populations. However, a growing body of research is elucidating the etiology of homesickness in younger populations, including children at summer camp, hospitalized children and students.

- Experience factors: Younger age; little previous experience away from home (for which age can be a proxy); little or no previous experience in the novel environment; little or no previous experience venturing out without primary caregivers.

- Attitude factors: The belief that homesickness will be strong; negative first impressions and low expectations for the new environment; perceived absence of social support; high perceived demands (e.g., on academic, vocational or sports performance); great perceived distance from home

- Personality factors: Insecure attachment relationship with primary caregivers; low perceived control over the timing and nature of the separation from home; anxious or depressed feelings in the months prior to the separation; low self-directedness; high harm avoidance; rigidity; a wishful-thinking coping style.

- Family factors: Low decision control (e.g., caregivers forcing a young child to spend time away from home against her wishes); governments forcing a person to be in a novel environment (e.g., being drafted into military service away from home or being sentenced to prison); unsupportive caregiving; caregivers who express anxiety or ambivalence about the separation (e.g., "Have a great time away. I don't know what I'll do without you.")

- Environmental factors: High cultural contrast (e.g., different language, customs, food); threats to physical and emotional safety; dramatic alternations in daily schedule; lack of information about the new place; perceived discrimination

Finally, research has provided no support for a few factors that conventional wisdom had once held to be risk factors. These include: recent separation or divorce of primary caregivers; geographic distance from home; or recent geographic move. Most likely, it is not a change in family structure, distance or dwelling that predicts homesickness, but whether these changes have left unanswered (potentially preoccupying) questions in the person's mind.

Because Coprolalia is such a severe form of Tourette Syndrome due to the type of tic involved, the social and societal aspects of a Coprolalia patient’s life can be very difficult. Oftentimes, the stigma and social maladjustment in Coprolalia can lead to social exclusion, bullying, and discrimination, which cause patients with severe symptoms to experience a negative impact on their health and wellbeing.[33]

According to Comorbidities, Social Impact, and Quality of Life in Tourette Syndrome, about one-third of Tourette Syndrome patients have been reported to have social problems, especially when they have Coprolalia. In agreement with this report, a study of Tourette Syndrome patients reported that the patients had problems with family relationships (29%), difficulties in making friends (27%), social life (20%), and being self-concious (15%). One theory behind these statistics is that Tourette Syndrome patients have higher rates of insecure peer attachments, problems in peer relationships, difficulty making friends, stigmatization, and lower levels of social functioning than their control counterparts. Along with this, a study including parents of Tourette Syndrome patients resulted in 70% of parents reporting at least one problem area when considering school, home, or social activities due to experiencing symptoms of isolation and trouble when encountering new people. [33]

At a more personal level, these patients have also expressed difficulty with self care, which tends to be heightened by the presence of a comorbidity such as ADHD and OCD. Along with this, those who also have ADHD exhibit an increase in behavioral problems and a poorer quality of life in relationship to their healthy counterparts along with their counterparts who have isolated Coprolalia. It is important to note however, that many of these social aspects of the life of a person with Coprolalia manifest more in younger patients and patients who also experience comorbidities.[34]

Some patients have been treated by injecting botulinum toxin (botox) near the vocal cords. This does not prevent the vocalizations, but the partial paralysis that results helps to control the volume of any outbursts. Surprisingly, botox injections result in more generalized relief of tics than the vocal relief expected.

The severity and frequency of outbursts can also be decreased by surgically disabling nuclei in the thalamus, the globus pallidus and the cingulate cortex.

A number of groups have been identified as being at greater risk of developing cannabis dependence and include adolescent populations, Aboriginal and Torres Strait Islanders (in Australia) and people suffering from mental health conditions.

Cannabis use disorder (CUD) (Also known as cannabis or marijuana addiction) is defined in the fifth revision of the "Diagnostic and Statistical Manual of Mental Disorders" (DSM-5) and ICD-10 published by World Health Organization as the continued use of cannabis despite clinically significant impairment, ranging from mild to severe.

Cannabis is one of the most widely used drugs in the world. In the United States, 49% of people have used cannabis. an estimated 9% of those who use cannabis develop dependence. In the US, , cannabis is the most commonly identified illicit substance used by people admitted to treatment facilities. Demand for treatment for cannabis use disorder increased internationally between 1995 and 2002.

Lavender foal syndrome (LFS), also called coat color dilution lethal (CCDL), is an autosomal recessive genetic disease that affects newborn foals of certain Arabian horse bloodlines. Affected LFS foals have severe neurological abnormalities, cannot stand, and require euthanasia shortly after birth. The popular name originates due to a diluted color of the foals coat, that in some cases appears to have a purple or lavender hue. However, not all foals possess the lavender coat colour, colouring can range from silver to light chestnut to a pale pink. Carrier horses have no clinical signs and DNA testing can determine if a horse carries the gene.

The condition has been recognized since the mid- to late-1950s.

Research into the genetics of LFS has been conducted at the University of California, Davis and Cornell University in the United States, the University of Queensland in Australia, and the University of Pretoria in South Africa. In November, 2009, Cornell University announced a DNA test has been developed to detect carriers of LFS. Simultaneously, the University of Pretoria also announced they had developed a DNA test. Testing is now available at Cornell, Pretoria, and Queensland, Australia.