In recent years the irreproducibility of preclinical studies has become a serious concern in drug developmental research. The findings of preclinical studies that cannot be reproduced are a drain on public resources and slow down the drug discovery process. Among the various factors that contribute to irreproducibility in preclinical drug developmental research, poor statistical analysis and weak experimental design play a major role in the failure of drugs in clinical research. Conclusion. Poor experimental design and lack of knowledge or limited knowledge of statistical analysis of data contribute significantly to the irreproducibility of preclinical research. A well-designed experiment with proper statistical analysis of data conducted by committed researchers rarely fails to reproduce.

The aim of this review is to describe key factors, such as poor statistical analysis and weak experimental design, that contribute to the irreproducibility of preclinical studies in drug development, and how such studies slow down the drug development process.

Brief description of the state of knowledge:
Theirreproducibility of preclinical research is a serious issue that researchers, especially those who are involved in drug discovery, are facing today. The irreproducibility of research drains public resources, time, and diminish the trust of the common man in the research community. The factors that contribute to the irreproducibility of preclinical research are related to experiment design and improper statistical analysis of the experimental data. Most of these factors can be eliminated by researchers developing a commitment to science and society.

Poor experimental design and lack of knowledge or limited knowledge of statistical analysis of data contribute significantly to the irreproducibility of preclinical research. A well-designed experiment with proper statistical analysis of data conducted by committed researchers rarely fails to reproduce.

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