Science for journalists
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Transcript of Science for journalists
Science for journalists
The MMR vaccine: a series of failures in science reporting
Combined MMR vaccine introduced
Measles vaccine introduced
MMR-autism link suggested
The MMR vaccine: the serious consequences of bad science reporting
BSE: The perils of communicating risk
Climate change: The perils of communicating uncertainty
Common misconceptions
Science advances by big breakthroughs
Progress is mostly slow and incremental
Science proves things Science gathers evidence
Scientists are neutral Scientists are human
“The Lone Genius” Science is carried out in collaboration
Scientists are always truthful “A scientist’s authority should command attention but, in the absence of evidence,
not belief”
famefundingprestige
timespace
interesteditorial
impact
scientist journalistpress officer
academic journal
From lab bench to front page
Observe
Hypothesise
Test
The Scientific Method
Observe
Hypothesise
Conclude
Common sense (or rationalism)
Designing a good experimental study: Does the MMR-vaccine cause autism?
• Experimental controls
• Size of study
• Statistical significance
• Random selection
• Measure other factors that might affect outcome
• Unbiased observations: double-blind
⇒Include subjects without vaccination
⇒The more, the better
⇒The likelihood that your results are luck
⇒To avoid confounding factors
⇒To detect possible confounding factors
⇒Neither the experimenter, nor the subject knows whether they are in the control group (placebo treatment)
How would we design an experiment to test whether MMR causes autism?
Wakefield et al. Uchiyama et al.
Experimental controls None +/- MMR jab+/- autism
Size of study 12 904
Statistical significance Not possible No significant correlation between vaccine and autism
Random selection No No
Measure other factors that might affect outcome
No Yes
Double blinded to remove bias
No Yes
Observe
Hypothesise
Scientific method
Wakefield et al. 1997
Test
Uchiyama et al. 2007
TitleA precise description of paper
AbstractA summary of what they did and what they found
IntroductionThe motivation and context of the research
MethodsAre they appropriate for the claims made?
ResultsTables, charts and lots of data
Discussion
The author’s views of what the results mean (or don’t)
How to read a scientific paper (on a deadline)
“Scientists constantly tell us contradictory stories”
http://www.dailymail.co.uk/health/index.html
How excited should I be?
Holy crap!
Yawn
Phase III (marketability)
Phase II (efficacy)
Phase I human trials (safety)
Animal tests
In vitro tests
Research announcement
Hypothesis
6/9/2010
Review articles: summarising the findings from literature
http://www.cochrane.org/
Systematic reviews: the gold standard
Dissecting a press release
Dissecting a press release
Source?•Preliminary study from conference, not peer-reviewedIs it a controlled experiment?•No comparison to non-diet drinksWhat do we know about type of drink?•Very few details on drinksWhat can you tell me about the subgroups?•Don’t know size of subgroups that drink a lot of diet drinksDoes the research prove diet drinks cause heart attacks? Can it?•Observational so can only show a link, not cause and effectHow do they know how much people drank?•Relies on self-reporting of diet, and only at start of study not as it goes alongWhat other risk factors were taken into account? •Controls for some factors but not all (family history of strokes? Other dietary habits? Weight gain?)What was the increase in heart attack risk?•Is it 61% or 48%?What is the baseline risk of heart attack? •Only relative risk given not absolute
Uncertainty in Science: Why won’t scientist give you a straight answer?
Statistical analysis
Observe
HypothesiseTest
“There’s a high probability that your
hypothesis is correct”
1. STATISTICAL SIGNIFICANCE
The scientists say: “The balance of evidence suggests that there is a discernible human influence on global climate"
Uncertainty in Science: Why won’t scientist give you a straight answer?
2. THE DEFINITIVE EXPERIMENTS ARE IMPOSSIBLE
CO2Do
manmade
emissionscause
global warming?
Uncertainty in Science: Why won’t scientist give you a straight answer?
3. IT’S IMPOSSIBLE TO PROVE THAT SOMETHING IS SAFE (BUT EASY TO SHOW THAT IT’S DANGEROUS)
What is the biological basis of consciousness?
Why is there more matter than antimatter?
Are there smaller building blocks than quarks?
Is ours the only universe?
Do mathematically interesting zero-value solutions of the Riemann zeta function all have the form a+bi?
Uncertainty in Science: Why won’t scientist give you a straight answer?
4. WE GENUINELY DON’T KNOW… YET
Balance in science reporting
Science Media CentreThere to help journalists who:
•Need a news interview with a scientist
•Have a question about a major science story
•Need a background briefing on a scientific topic
Sense About ScienceThere to:
•Respond to inaccuracies in claims about science
•Help those who need expert help contact scientists about issues of importance
•Brief non-specialists on scientific developments and practices
Useful organisations and further info
PubMedUS National Library of Medicine
Free search tool for finding PEER-REVIEWED scientific studies
The Cochrane CollaborationLibrary of systematic reviews in healthcare
European Food Safety AuthorityLibrary of systematic reviews of nutrition and health claims for foods
Useful resources: science publication databases