Quantifying Clinical Relevance in the Treatment of Schizophrenia

Background: To optimize the management of patients with schizophrenia, quantification of treatment effects is crucial. While in research studies, the use of quantitative assessments is ubiquitous, this is not the case in routine clinical practice, creating an important translational practice gap. Objective: The aim of this study was to examine the relevance, methodology, reporting, and application of measurement-based approaches in the management of schizophrenia. Methods: We summarized methodological aspects in the assessment of therapeutic and adverse antipsychotic effects in schizophrenia, including definitions and methods of measurement-based assessments and factors that can interfere with the valid quantification of treatment effects. Finally, we proposed pragmatic and clinically meaningful ways to measure and report treatment outcomes. Results: Although rating scales are ubiquitous in schizophrenia research and provide the evidence base for treatment guidelines, time constraints and lack of familiarity with and/or training in validated assessment tools limit their routine clinical use. Simple but valid assessment instruments need to be developed and implemented to bridge this research-practice gap. In addition, results from research trials need to be communicated in clinically meaningful ways, including the reporting of effect sizes, numbers-needed-to-treat and -harm, confidence intervals, and absolute risk differences. Some important outcomes, such as treatment response, should be reported in escalating intervals using incrementally more stringent psychopathology improvements. Even with quantification, it remains challenging to weigh individual efficacy and adverse effect outcomes against one another and decide on the targeted or desired improvement or outcomes while also incorporating these in patient-centered and shared decision methods. Conclusions: Quantification of treatment effects in schizophrenia is relevant for patient management, research, and the evaluation of health care systems. Beyond consensus about meaningful outcomes definitions, reporting strategies, pragmatic tool development and implementation, the discovery of novel treatment mechanisms and related biomarkers is hoped to advance measurement-based approaches in schizophrenia and thereby improve patient outcomes.