Measuring Psychosis: A Review of Widely Used Clinical Outcome Assessments in Clinical Trials
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Abstract
Accurate diagnosis and assessment of symptoms is essential to the appropriate treatment and management of individuals with psychotic disorders. It also plays a pivotal role in research, ensuring that enrolled subjects meet study-specific inclusion requirements and that their progress is accurately tracked throughout the study. Clinical outcome assessments are standardized instruments designed specifically to measure symptoms and their impact on a patient’s life and functioning. These instruments can be used to diagnose, categorize, and track symptom severity, and to measure the functional impact of disease on a patient’s quality of life. Clinical outcome assessments play a pivotal role in advancing our understanding and treatment of schizophrenia and other psychotic disorders, providing the ability to evaluate the safety and efficacy of emerging treatments and interventions. In this review article we provide an overview of the most widely used clinical outcome assessments in schizophrenia and other psychotic disorders research with a focus on clinical trials, and delve into the specific instruments commonly used to diagnose, measure symptom severity, and assess cognitive ability. A brief description of each instrument and its role in clinical outcome assessment is provided, along with advantages and limitations in implementation. Additionally, the clinician’s perspective on the administration and scoring of these scales is included, where relevant. The goal is to familiarize new clinicians and researchers with the available assessment tools, highlighting the advantages, limitations, and any other relevant information that can aid in the selection of the appropriate measurement tools for their patients and studies. Finally, we briefly discuss our view on the future of clinical outcome assessments in schizophrenia and other psychotic disorders research and clinical trials.
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