Evaluating the relaxation effects of Shikuwasa (Citrus depressa Hayata) essential oil inhalation in young female adults: Study protocol for a randomised controlled trial
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引用次数: 0
Abstract
Introduction
The essential oil of Shikuwasa (Citrus depressa Hayata) primarily contains limonene and γ-terpinene, which have potential applications in stress management and relaxation. However, the psychological or physiological relaxation effects of Shikuwasa essential oil on humans are still unknown. This study aims to investigate the short-term relaxation effects of Shikuwasa essential oil, one of the less-studied varieties, compared to inhaling odour-free air in young female adults.
Methods
and analysis: This study is a two-arm, parallel-group, open-label, randomised controlled superiority trial. Forty young female adults will be assigned with a 1:1 allocation ratio to either the Shikuwasa essential oil inhalation group or the odour-free air inhalation group. The primary outcome measure will be subjective tense arousal (subscale of the Japanese version of the University of Wales Institute of Science and Technology Mood Adjective Checklist). Secondary outcomes include objective measures: miosis rate and peripheral skin temperature for evaluating autonomic nervous activity, and cerebral blood flow (assessed using near-infrared spectroscopy) for evaluating central nervous activity. Since these objective outcome measures cannot be performed at the same time, we divide our experiment into three phases and participants will inhale sample vials for 2 min in each experiment. We will also evaluate individual preferences/impressions regarding inhaled samples and any adverse events.
Ethics and dissemination
The study protocol has been reviewed and approved by the Research Ethics Committee of the Faculty of Medicine, University of Miyazaki (reference no: I-0074). The findings of this study will be disseminated to academic and professional audiences via publications in peer-reviewed journals and presentations at academic conferences, and to the broader public via public talks and media/press releases. All study findings, whether negative or positive, will be reported.
Trial registration
UMIN Clinical Trials Registry (UMIN-CTR), UMIN000053914. Prospectively registered on March 20, 2024.
期刊介绍:
Contemporary Clinical Trials Communications is an international peer reviewed open access journal that publishes articles pertaining to all aspects of clinical trials, including, but not limited to, design, conduct, analysis, regulation and ethics. Manuscripts submitted should appeal to a readership drawn from a wide range of disciplines including medicine, life science, pharmaceutical science, biostatistics, epidemiology, computer science, management science, behavioral science, and bioethics. Contemporary Clinical Trials Communications is unique in that it is outside the confines of disease specifications, and it strives to increase the transparency of medical research and reduce publication bias by publishing scientifically valid original research findings irrespective of their perceived importance, significance or impact. Both randomized and non-randomized trials are within the scope of the Journal. Some common topics include trial design rationale and methods, operational methodologies and challenges, and positive and negative trial results. In addition to original research, the Journal also welcomes other types of communications including, but are not limited to, methodology reviews, perspectives and discussions. Through timely dissemination of advances in clinical trials, the goal of Contemporary Clinical Trials Communications is to serve as a platform to enhance the communication and collaboration within the global clinical trials community that ultimately advances this field of research for the benefit of patients.