"Only schizoid patients", suggests Klein, "who have worked through the abandonment depression ... ultimately will believe that the capacity for relatedness and the wish for relatedness are woven into the structure of their beings, that they are truly part of who the patients are and what they contain as human beings. It is this sense that finally allows the schizoid patient to feel the most intimate sense of being connected with humanity more generally, and with another person more personally. For the schizoid patient, this degree of certainty is the most gratifying revelation, and a profound new organizer of the self experience. ": 127

Development and course
SzPD 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 is usually chronic and long-lasting mental conditions, SzPD is not expected to improve with time without treatment; however, much remains unknown because it is rarely encountered in clinical settings. Epidemiology
SzPD is uncommon in clinical settings (about 2.2%) and occurs more commonly in males. It is rare compared with other personality disorders, with a prevalence estimated at less than 1% of the general population.Philip Manfield suggests that the "schizoid condition", which roughly includes the DSM schizoid, avoidant and schizotypal personality disorders, is represented by "as many as forty percent of all personality disorders."
Manfield adds "This huge discrepancy [from the ten percent reported by therapists for the condition] is probably largely because someone with a schizoid disorder is less likely to seek treatment than someone with other axis-II disorders. "A 2008 study assessing personality and mood disorder prevalence among homeless people at New York City drop-in centres reported an SzPD rate of 65% among this sample. The study did not assess homeless people who did not show up at drop-in centres, and the rates of most other personality and mood disorders within the drop-in centres was lower than that of SzPD. The authors noted the limitations of the study, including the higher male-to-female ratio in the sample and the absence of subjects outside the support system or receiving other support (e.g., shelters) as well as the absence of subjects in geographical settings outside New York City, a large city often considered a magnet for disenfranchised people.A University of Colorado Colorado Springs study comparing personality disorders and Myers–Briggs Type Indicator types found that the disorder had a significant correlation with the Introverted (I) and Thinking (T) preferences. History
The term "schizoid" was coined in 1908 by Eugen Bleuler to designate a human tendency to direct attention toward ones inner life and away from the external world, a concept akin to introversion in that it was not viewed in terms of psychopathology. Bleuler labeled the exaggeration of this tendency the "schizoid personality".