Methodological and reporting recommendations for clinical trials in Nutritional Psychiatry: guidelines from the International Society for Nutritional Psychiatry Research

Research on nutraceutical and dietary interventions in psychiatry has grown substantially, but progress is hindered by methodological inconsistencies and limited reporting standards. To address this, the International Society for Nutritional Psychiatry Research presents the first guidelines on clinical trial design, conduct, and reporting for future clinical trials in this area. Recommendations were developed using a Delphi process including eighteen researchers with considerable clinical trial expertise and experience in either methodology, nutraceutical, or dietary interventions in psychiatry. These guidelines provide forty-nine recommendations for clinical trial design and outcomes, five for trial reporting, and seven for future research priorities. The recommendations included in these guidelines are designed to inform both nutraceutical and dietary clinical trial interventions in Nutritional Psychiatry. Common themes include an emphasis on the importance of a multidisciplinary research team and integration of co-design processes into the conduct and design of clinical research, methods to improve transparency and replicability of trial outcomes, and measures to address common biases in nutrition trials. Furthermore, we provide recommendations for future research including examining a greater variety of nutraceutical and dietary interventions, scalable delivery models, effectiveness and implementation studies, and the need to investigate these interventions in the prevention and management of less studied psychiatric conditions (e.g. schizophrenia and bipolar disorder). Recommendations included within these guidelines are intended to improve the rigor and clinical relevance of ongoing and future clinical trials in Nutritional Psychiatry.