I studied statistics nearly all my life, and even then, this book was an enlightenment to me. I would recommend it not only to biostatistocians, but also for other fields where statistics is heavily used.
I bought this book as a recommendation from my supervisor, who owns a previous edition. But after I started reading it, and tell him the concepts, and why our data looked like it did, and why we did not get significant results or why we did get it, and whats a true meaning of t-statistics, and the theory behind confidence intervals, we decided to compare the versions, and we realized that first edition was way more formal and mathematical. So now he ordered this new addition too.
There are nearly no formulas in the book, it is very easy to read from head to tail. It's almost like reading a novel!
I am already half way through and I am very looking forward for the next chapter, which in fact never happened to me when reading a scientific material. Also, Q&A section is very nice, where you can check your understanding of concepts, or just see the correct answers to tricky questions.