An understanding of biostatistics is necessary for reading and comprehending published literature, for performing retrospective research, and for designing and analyzing prospective clinical trials. Biostatistical concepts are also tested on oncology board exams. This book is organized into four sections covering 13 chapters. Section I begins with the basic foundations of biostatistics that are tested on board exams such as summarizing and graphing data, sampling, and statistical estimation. In Section II, these basics are then expanded on to include the concepts used in retrospective study design, analysis, and interpretation. It discusses hypothesis testing, correlation, regression, categorical data analysis, survival analysis methods, and noninferiority analysis. Section III focuses on prospective clinical trials, guiding readers in their understanding of published clinical trials and in the design and analysis of novel clinical trials. It describes cohort studies, case-control studies, cross-sectional studies, matched studies, analysis of studies, and sample size. The final section presents self-study multiple choice questions with answers and rationales.