Journal of Clinical Trials
Open Access
ISSN: 2167-0870
ISSN: 2167-0870
Department of Health Promotion, National Institute of Public Health, Wako City, Saitama 3510197, Japan
Research Article
Risk of Bias in Clinical Trials Reported for Foods with Functional Claims in Japan: A Cross-Sectional Study on Research Quality
Author(s): Hiroharu Kamioka*, Hideki Origasa, Jun Kitayuguchi, Takahiro Yoshizaki, Mikiko Shimada, Yasuyo Wada, Hiromi Takano-Ohmuro and Kiichiro Tsutani
Background: The Foods with Function Claims (FFC) notification system was introduced in Japan in April 2015. We
hypothesized that there would be risk of bias (RoB) specific to health food interventions. The purpose of this cross-sectional
study was to clarify RoB and related factors of clinical trials (CTs) reported as the scientific basis of efficacy in the FFC.
Methods: All 103 articles based on CTs published on the Consumer Affairs Agency website from 1 July 2018 to 30 June
2021 were reviewed. We evaluated 14 items, the highest RoB: 14 points (pts), as well as related items including first author
characteristics, journal name, year published, journal impact factor, article language, and name of clinical trial registration.
Results: The RoB score was 5.7 ± 2.5 pts. In general, there was a remarkable.. View More»