based on patient outcomes research, but was caused by poorly defined criteria interacting with clinical tradition and belief; clinician enculturation with unscientific assumptions from the diagnosis' history (discussed above), including the invalid kraepelinian dichotomy; and by clinicians being unfamiliar with the scientific limitations of the diagnostic and classification system. the dsm-5 schizoaffective disorder workgroup analyzed all of the available research evidence on schizoaffective disorder, and concluded that "presenting symptoms of psychosis have little validity in determining diagnosis, prognosis, or treatment response." given our understanding of overlapping genetics in bipolar disorders, schizoaffective disorder, and schizophrenia, as well as the overlap in treatments for these disorders; but given the lack of specificity of presenting symptoms for determining diagnosis, prognosis or treatment response in these psychotic illness syndromes, the limits of our knowledge are clearer: presenting symptoms of psychosis describe only presenting symptoms to be treated, and not much more. schizoaffective disorder was changed to a longitudinal or life course diagnosis in dsm-5 for this reason. research little is known of the causes and mechanisms that lead to the development of schizoaffective disorder. whether schizoaffective disorder is a variant of schizophrenia (as in dsm-5 and icd-10 classification systems), a variant of bipolar disorder, or part of a dimensional continuum between psychotic depression, bipolar disorders and schizophrenia is currently being investigated. more recently, some research suggests the need for a more specialized classification for schizoaffective disorder. in a 2017 examining diagnostic heterogeneity study, researchers found that when compared to a schizophrenia sample, individuals with schizoaffective disorder rate higher in suicidality and anxiety disorder comorbidity.