This highly successful guide, now in its firth edition with sales in excess of 26,000, is essential reading for all those requiring a basic understanding of epidemiology-the study of how often and why diseases occur in different groups of people.

Assuming no prior knowledge of the subject, it guides the novice through both the theory and practical pitfalls with the aid of familiar examples.

Subjects covered include:
What is Epidemiology?
Quantifiying Disease in Populations
Comparing Disease Rates
Measurement Error and Bias
Planning and Conducting a Survey
Ecological Studies
Longitudinal Studies
Case-control and Cross Sectional Studies
Experimental Studies
Screening
Outbreaks of Disease
Reading Epidemiolgical Reports

This concise and readable book, now revised and updated, is an invaluable tool for all health care professionals and medical students whether they are getting to grips with epidemiology for the first time or as a practical revision aid for those needing to refresh or update their knowledge.