Medical textbooks in this era of evidence-based medicine tend to concentrate more on statistical analysis than on the quality of the data collected. Machin and Campbell (health and related sciences, U. of Sheffield, UK) emphasize the importance of good design in health surveys, epidemiological research, clinical trials, and validation studies treating diagnostic and prognostic factors. The guide features study examples and standard statistical tables. Machin is also affiliated with the UK Children's Cancer Study Group and National Cancer Centre, Singapore.