Preface to the Fourth Edition
This book is designed to serve as a textbook for a one-semester course in biostatistics
for students or reseachers in the biomedical field. We have also included material that
will be useful to physicians, public health workers, and nurses who become involved
in research projects and wish not to only understand the basic concepts of biostatistics
but also to apply them in their research projects.
The mathematics level has been kept deliberately low. We have provided formulas
and examples so that the reader can see how to make the calculations, as this is useful
in understanding what is done. References are provided for statistical programs that
will perform the calculations and graphs for use in research projects.
In line with the dual purpose of including teaching the basic concepts and also
including material that is essential in performing research projects successfully, two
types of chapters are included. One type is concentrated on basic statistical techniques
that are widely used in biomedical and public health research. These include a new
chapter that presents the more widely used nonparametric tests. The second type,
which includes material useful in performing research projects, is represented in
Chapters 1 and 3. In Chapter 1 we present the initial steps in designing a biomedical
study and describe the common types of biomedical studies. Chapter 3 is a new
chapter that was not in our previous editions. It gives the initial steps in planning
a biomedical or public health study, including deciding what data to take, how to
collect it, and how to test the data collection method. Brief introductions to data entry
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