Find more at Teaching Science This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License. Attribution — You must attribute the work in the manner specified by the author or licensor (but not in any way that suggests that they endorse you or your use of the work). Noncommercial — You may not use this work for commercial purposes. Share Alike — If you alter, transform, or build upon this work, you may distribute the resulting work only under the same or similar license to this one. Find more at Teaching Science

Immunisation 3/5 Data In Context

Which School? You are a parent trying to choose between two schools by looking at their exam results. 25 students from Grange Hill got an A* in science last year. 44 students from Springfield School reached the same grade. Which do you choose and why?

Implanon Each group will need to read and discuss a news story, then: Use what you are given to write a short paragraph on the effectiveness of Implanon. Choose whether you would recommend Impanon to a friend based on the information in the news story.

Implanon vs alternatives The contraceptive pill has an accepted success rate of 99% when used correctly. The equivalent rate for condoms is 98%. Give advantages and disadvantages of Implanon compared to these two methods. Which of the three would you recommend to: A 19 year old university student A 30-year old female in a long-term relationship

Comparing Stories What about differences between how the story was reported? You have five minutes to compare the summaries you have written with those from other groups. Can you explain any of the differences by referring to the original news stories?

Implanon Summary Most stories quoted the figure of ~600 women who became pregnant while using it. Some also mentioned that there had been over 1600 reports of other problems. Very few stories included the total of women using it or showed in their coverage that the success rate was more than 99.9%.

Context of MMR When investigating any possible link between the MMR vaccination and a rise in autism rates, we also need to understand the context. How serious are measles, mumps and rubella? What is happening to autism rates generally?

Measles, Mumps and Rubella Complications and severe symptoms occur in about 0.1% of measles (including brain damage and death) Between 1 and 10% of mumps cases lead to meningitis or sterility (more often in adults) Complication in rubella are very rare for children and adults but it often causes brain damage to a foetus if a woman catches it while pregnant.

Autism... is a complex condition but usually includes difficulties relating to the world, especially other people. was first described in the 1940s. has no known common cause. is diagnosed in around 0.1% of people (in UK). is thought to be related to the more common Asperger’s Syndrome (up to 0.6 % in UK).

Autism in USA (cases per 1000) Can you suggest any explanations for the increased prevalence this data shows?

A Link to MMR? If a link was present, we would expect that as numbers of children vaccinated increased, so would the number of diagnoses of autism. Rates would vary between vaccinated and non-vaccinated groups. We would expect to see increasing numbers of autism diagnoses when countries introduced the MMR vaccination (and new autism cases would decrease when removed).

Evidence? None of these links have been demonstrated. In the developed world children receive vaccinations, including MMR, around the same time as symptoms of autism develop. Rates of autism diagnosis are increasing but we are not sure if this is because it is more common or because of better diagnosis.

Infections vs Vaccines A clear link between vaccinations and reduced cases has been demonstrated.

Skeptics Say... “The plural of anecdote is not data.” What does this mean? Can you suggest why people will often rely more on anecdotes than data? Can you give examples of how companies use this?