Schizophrenia is a chronic and severe mental disorder that significantly affects how a person thinks, feels, and behaves. It is characterized by a range of symptoms including delusions, hallucinations, disorganized speech and behavior, and cognitive impairments. Despite advances in psychiatric medicine, schizophrenia remains one of the most disabling mental illnesses, with onset typically occurring in late adolescence or early adulthood. The exact cause is multifactorial, involving genetic, neurobiological, and environmental factors. Accurate diagnosis is crucial for effective treatment and long-term management, yet remains challenging due to the overlap of symptoms with other psychiatric conditions. This article explores the clinical manifestations, diagnostic criteria, and assessment methods for schizophrenia, drawing from recent literature and global clinical guidelines. It highlights the importance of early detection, the role of neuroimaging and psychometric tools, and the relevance of DSM-5 and ICD-11 diagnostic systems. The article uses a qualitative review methodology to analyze scholarly sources and concludes with recommendations for improving diagnostic accuracy and patient outcomes. Understanding schizophrenia and its diagnostic challenges is essential for mental health professionals, caregivers, and policy-makers seeking to enhance psychiatric care and reduce the social stigma associated with the illness.

Schizophrenia, psychosis, diagnosis, DSM-5, ICD-11, delusions, hallucinations, mental illness, psychiatry, neurobiology.

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