The Questions and Answers Book on Statistics for Clinical Researchers: 262 questions for deeper statistical learning through questioning

There are three important questions for the readers to understand the motivation for this book: Why was this book written? What is this book about? And how should this book be read? Why was this book written? We first need to understand the basic learning principles to answer this question. If we can summarize in one sentence, it would be: learning comes from within. It means that we learn what is important to us. We learn what we are curious about. We learn when we connect the knowledge. Taken all together, you can agree with us that the questions are fundamental as they guide our learning. Let me make an analogy here. Suppose you are assembling a jigsaw puzzle. What is the best way? If someone gives you a random piece or asks for a certain piece (for instance, a piece for the corner that is dark blue as this is for the sky). The answer is the latter. And this is how the building of our knowledge works. When we are given random "pieces" of knowledge, they do not attach to our main knowledge, and we quickly forget about them. But when we receive the piece we are looking for, our knowledge and understanding increase significantly. This is the goal of writing this book, to help you find the pieces you need to build your knowledge of statistics. Here the reader could say: but the readers should send their questions in this case. Our solution was then to analyze thousands of questions we receive every year from our students to learn what our students were asking. What is this book about? This book is to help you to create your knowledge in statistics. Given we have students with a diverse background in statistics: from little to no knowledge of statistics to more advanced knowledge, the questions we created are based on all these levels. We hope to cover most of the questions you may have on the topics we discuss here. Is this a good book if this is your first encounter with statistics? Yes. But, in this case, we would also recommend using this book along with your course of statistics or another textbook. Though for some readers beginning in this field, this book alone may be enough to learn more. We choose to answer the questions in a simple way to be reachable no matter your level of expertise. We aimed to offer guidance through simplicity, refined ideas, creating examples, and graphics. In that sense, we hope you benefit from our explanations and engage you in a learning journey with this book. How to use this book? This book answers real questions that we have received based on our experience with about 15 years of the Principles and Practice of Clinical Research program. Among the topics, we covered the introduction to statistics, basics of clinical research, relevant statistical concepts, parametric and non-parametric tests, sample size calculation, meta-analysis and subgroup analysis, linear and logistic regression, missing data, and covariate adjustment, survival analysis, and lastly, observational studies and confounding. We selected carefully and included the most common and relevant questions from the Statistical modules. Furthermore, each chapter contains a short introduction and review of the topic. This book will provide you with the skills to understand statistics, apply them to your research and daily practice, and design a proper study.