This book is written on pedagogic principles. Basically, there are three elements t address the subject concerned: the first being the study notes, i.e., theory; th second is the exercises (problem based learning) that accompany each chapter, i.e. each chapter is accompanied with related exercises. These exercises encourage students/readers to use their acquired knowledge about the subject or topic; the third part is contained with MCQs (Multiple Choice Questions) which play the same role and are on the same level that the students may expect to encounter in thei professional examinations.Each chapter represents the state of art knowledge. The language of the book is very simple and easy to understand the subject matter.Prof. (Dr.) K.S. Negi, has experienced of 30 years of teaching and research experience in the field of medical statistics. He has numerous research publications to his credit and acts as a consultant for several research projects. He has been actively involved in various I.C.M.R. projects in the Institute of Medical Sciences, Banaras Hindu University, Varanasi (1981 to1995). Dr. Negi has worked as a professor in HIMS, Jollygrant Dehradun (1996 to 2012). He joined as a Professor (Biostatistics) in GMC, Pokhra,Dehradun (U.K).Nepal (2012 to 2013). Currently