One type of early intervention is primary prevention, which is either testing or universal intervention for the entire population or prevention for possible causes such as childbirth or even pregnancy complications, which is less specific. The other is aimed at high-risk groups. This article focuses on the second type of early intervention. Early intervention involves two main issues: how to identify at-risk groups and how to intervene effectively and reasonably. The intervention methods currently used in relevant studies are mainly psychosocial and pharmacological interventions. Schizophrenia is a chronic psychiatric disorder of unknown etiology, most often starting in young adults, with three main symptoms: positive symptoms, negative symptoms, and impairment of cognitive function. Patients have varying degrees of impairment in social functioning, and the treatment outcomes and prognosis are unsatisfactory, imposing a great burden on families and society. Therefore, many researchers have envisioned whether early intervention in schizophrenia would result in better outcomes and prognosis. There is now a growing body of relevant evidence to support this hypothesis. Most patients in the clinical setting present to the hospital with significant symptoms. A growing body of evidence finds that the vast majority of patients have had a period of prodromal symptoms preceding the onset of schizophrenia and are accompanied by changes in the neurobiology of the brain and a decline in cognitive function. How to identify people at risk for schizophrenia There is not yet a very definitive identification method. Genetic methods are a well-known way to identify people at risk, but the heritability is only 11-37%, which leaves a large false-positive rate and raises many ethical issues, especially in those who are underage and have prodromal symptoms. In contrast, the sensitivity and specificity of the chosen clinical approach is relatively high, but only if the disease process has already started and identification is possible. There are two main concepts of identification methods used in most early intervention studies today: the high-risk factor approach and the underlying symptom approach. These two criteria are described below. High-risk factor criteria The current method commonly used to identify people at risk, especially in drug intervention studies, consists of three criteria: AttenuatedpositivesymptomsAPS: including peculiar thought content or implicated ideas, suspicion, exaggeration, perceptual disturbances or hallucinations and bizarre behavior or dressing. At least one of these symptoms must be present multiple times per week or for a specific period of time lasting 1 week, which varies from study to study and ranges from 3 months to 1 year. Transient psychotic symptoms: similar to the definition of transient psychosis in DSMIV (hallucinations, delusions and thought form disorders), with symptoms resolving spontaneously within 1 week. Criteria for status and trait risk factors included: altered mental status or a recent reduction of at least 30 points on the Gross Abilities Scale (GAF), plus more than one of the following risk factors: more than one first-degree relative diagnosed with any of the DSM?IV psychiatric disorders, or schizotypal personality disorder. High-risk factor labeling has been used in many early intervention studies, and 41% of those meeting this criterion developed acute psychosis 12 months later. This terminology is characterized by the fact that it does not imply a certainty of developing a disorder such as schizophrenia, but rather suggests an existing psychological state that puts them at risk for developing schizophrenia. cases leads to ethical issues. On the other hand, they are subjects who participate in the high-risk population model voluntarily. They were aware of the mental changes and functional alterations. Thus, although there are false positives, they are all “cases” that need help. Basic symptoms are minor, often self-perceived, perceptual or cognitive deficits, and in the Bonn Early Cognition Study, if at least one symptom was present on the 66-item Bonn Basic Symptom Scale at baseline, the odds of developing schizophrenia were 78%. The average duration was 4 years. A minimum of 25% of patients with a final diagnosis of schizophrenia had these symptoms, with a positive rate of >70%. The 10 basic symptoms reflecting information processing disorders had high positivity and specificity and a low false positive rate (approximately 1.9% to 7.5%). This set of symptoms constitutes the main part of the “early prodromal symptoms”. Schizotypy Schizotypy was introduced by Meehl in 1962 to describe the genetic susceptibility to schizophrenia in people who are not biologically related to schizophrenia and who may eventually develop schizotypal personality disorder or schizophrenia, depending on environmental factors. 40 years later, research has found that schizotypy may be a clinical outcome. Schizotypy is now considered to have the following characteristics: first, psychotic signs or symptoms; second, negative symptoms such as withdrawal, withdrawal and abnormal emotional experiences. Neuropsychological deficits: with varying degrees of impairment in attention, memory and executive functioning, schizotypy is a syndrome of mild abnormalities in brain function. Discussion It has been decades since early intervention for schizophrenia was first proposed, but no groundbreaking conclusions have been reached and many questions remain. First, there is no uniform definition of at-risk individuals, and it remains to be discussed whether to base the definition on clinical symptoms or also on some biological markers. Most of the previous relevant studies have basically used criteria for identifying early schizophrenia around clinical manifestations, such as prodromal symptoms or similar symptoms. The sensitivity and specificity of this approach is not very high and therefore there is a risk of false positives, which raises some associated ethical issues. The recent use of introducing schizotypy into early intervention in schizophrenia is an innovation. One of the keys to the prevention of schizophrenia is the identification of abnormal manifestations in the pathogenic process reflecting the causative pathology, meaning that in addition to the assessment of clinical symptoms, it is also necessary to assess those dysfunctions that are similar to the clinical symptoms in the pathogenic process that eventually triggers schizophrenia. In fact, a significant flaw in the reliability of prodromal symptoms is that they usually reflect only relatively weak effects of the pathogenic process, which is related to their lack of correlation with prognostic specificity Applying this concept to early intervention in schizophrenia may lead to a greater breakthrough. And here is where the definition of schizotypy differs from the clinical presentation definition of a high-risk population in its ability to predict neuropsychological, neuroimaging, or psychophysiological findings consistent with what we know about the neurobiological features of schizophrenia. But the validity for schizotypy needs to be confirmed. Second, it is still worth exploring how to perform safe and effective early interventions for high-risk groups. Because second-generation antipsychotics have few side effects and are thought to have a large effect on cognitive function and negative symptoms, they are currently considered the most likely to be used as early pharmacological interventions; olanzapine, and risperidone have been used, but the evaluation criteria for the optimal dose and the effects of these drugs vary, and there is a lack of multicenter On the other hand, whether there are potential side effects, such as causing metabolic problems, has not been evaluated.