Every day we read or hear about new health research that looks at what might help or harm, limit or extend our lives. Health research is big business and over a million papers are published every year on health-related topics. So how do we find the evidence we need and, much more important, how do we judge how good that evidence is? Over four weeks, this free online course will: look at the factors that affect the reliability of evidence; provide practical help on how to find the best evidence; improve your understanding of the terminology of health research; and give you some simple tools to help judge whether you can believe it. The issues raised in the course are examined in a series of weekly case studies which provide a framework to discuss wider issues with health research. Topics include the Measles-Mumps-Rubella (MMR) vaccine, the use of drugs in pregnancy and the impact of dehydration on our ability to function. As part of the course, we want to develop a freely-available resource bank that points people to sources of good evidence throughout the world. As a learner, we would like you to be involved in this, by identifying the best evidence-based health resources in your country and acting as a quality checker. The team of educators on the course come from a range of disciplines, including health, social sciences and journalism, and teach courses at all levels on how to understand research and use it effectively.