Precision for binary measurement methods and results under beta-binomial distributions

To handle typical problems from fields dealing with biological responses, this study develops a new statistical model and method for analysing the precision of binary measurement methods and results from collaborative studies. The model is based on beta-binomial distributions. In other words, we assume that the sensitivity of each laboratory obeys a beta distribution and the binary measurement results under a given sensitivity follow a binomial distribution. We propose the key precision indicators of repeatability and reproducibility for the model and derive their unbiased estimates. We further propose a confidence interval for repeatability by applying the Jeffreys interval, which utilizes the assumption of beta distributions for sensitivity. Moreover, we propose a statistical test for determining laboratory effects, using simultaneous confidence intervals based on the confidence interval of each laboratory's sensitivity. Finally, we apply the proposed method to real-world examples in the fields of food safety and chemical risk assessment and management

鉛はんだ代替におけるリスクトレードオフ評価のための用量反応関係の導出

要旨あり環境リスクと統計解析 －データ基盤構築と解析－原著論

Identification of RNA biomarkers for chemical safety screening in mouse embryonic stem cells using RNA deep sequencing analysis

Although it is not yet possible to replace in vivo animal testing completely, the need for a more efficient method for toxicity testing, such as an in vitro cell-based assay, has been widely acknowledged. Previous studies have focused on mRNAs as biomarkers; however, recent studies have revealed that non-coding RNAs (ncRNAs) are also efficient novel biomarkers for toxicity testing. Here, we used deep sequencing analysis (RNA-seq) to identify novel RNA biomarkers, including ncRNAs, that exhibited a substantial response to general chemical toxicity from nine chemicals, and to benzene toxicity specifically. The nine chemicals are listed in the Japan Pollutant Release and Transfer Register as class I designated chemical substances. We used undifferentiated mouse embryonic stem cells (mESCs) as a simplified cell-based toxicity assay. RNA-seq revealed that many mRNAs and ncRNAs responded substantially to the chemical compounds in mESCs. This finding indicates that ncRNAs can be used as novel RNA biomarkers for chemical safety screening