1. Numbers need
Context

2. Although not everyone might agree,
Statistics are…

3. Although not everyone might agree,
Statistics are…
Interesting

4. Although not everyone might agree,
Statistics are…
Interesting Educational

5. Although not everyone might agree,
Statistics are…
Interesting Educational Important

6. But it can often be hard to
understand them without CONTEXT

7. Our media
abounds
with context-less
numbers

8. Let’s take a look at a few…

9. “Bacon increases risk of
colorectal cancer by 20%”

10. “Bacon increases risk of
colorectal cancer by 20%”
“1 extra unit of alcohol a day
increases a woman’s risk of
breast cancer by 12%”

11. “Bacon increases risk of
colorectal cancer by 20%”
“1 extra unit of alcohol a day
increases a woman’s risk of
breast cancer by 12%”
“Just 2 units of alcohol a day
reduces risk of heart disease
by 17%”

12. But what do the
percentages really
mean in real life?

13. And is there a more
relevant way we could
be describing this
information

14. “Bacon increases risk of
Colorectal cancer by 20%”

15. But just how bad is that?

16. Lets assume that ordinarily
5 out of 100 people develop
Colorectal cancer.

17. Therefore if all 100 ate 3 extra
rashers every day...
The number could rise to six

18. Therefore if all 100 ate 3 extra
rashers every day...
The number could rise to six

19. So therefore…

20. Bacon increases
So therefore… risk of Colorectal
cancer by 20%

21. Bacon increases
So therefore… risk of Colorectal
cancer by 20%
Is the exact
same as saying

22. Bacon increases
So therefore… risk of Colorectal
cancer by 20%
About
Is the exact
1 extra case per
same as saying
100 people

23. Next up…

24. “One extra unit of alcohol a day
increases a woman's risk of
breast cancer by 12%”

25. But just how bad is that?

26. Let’s assume about 10 out of 100
women have breast cancer in a
lifetime

27. If all 100 drink an extra unit a day,
that number rises to 11.

28. If all 100 drink an extra unit a day,
that number rises to 11.

29. So therefore…

30. One extra unit of
alcohol a day increases
So therefore… a woman's risk of breast
cancer by 12%”

31. One extra unit of
alcohol a day increases
So therefore… a woman's risk of breast
cancer by 12%”
Is the exact
same as saying

32. One extra unit of
alcohol a day increases
So therefore… a woman's risk of breast
cancer by 12%”
About
Is the exact
1 extra case per
same as saying
100 people

33. And Finally…

34. “Just two units a day reduces risk
of heart disease by 17%”

35. But just how GOOD is that?

36. About 32 out of 100 women have
coronary heart disease in a lifetime.

37. If all 100 were to drink 2 units of
alcohol every day… that number
would fall to 27

38. If all 100 were to drink 2 units of
alcohol every day… that number
would fall to 27

39. So therefore…

40. Just two units a day
So therefore… reduces risk of heart
disease by 17%

41. Just two units a day
So therefore… reduces risk of heart
disease by 17%
Is the exact same
as saying

42. Just two units a day
So therefore… reduces risk of heart
disease by 17%
About
Is the exact same
5 fewer cases per
as saying
100 people

43. So we have a little problem

44. Depending on the story

45. 20% can equal
1 person in 100

46. 20% can equal
1 person in 100
12% can equal
1 person in 100

47. 20% can equal
1 person in 100
12% can equal
1 person in 100
17% can equal
5 people in 100

48. So…

49. Percentage figures without
CONTEXT are meaningless and
can often misleading

50. When talking about health
matters it isn’t enough to deal
with percentages

51. Think about number of
lives affected

52. And…

53. We must hold our media to
account and ensure that
journalists do not go for the
FLASHY, SHINY and TRENDY
(not to mention misleading) sounding story
rather than the more relevant
and helpful one...

54. Because…

55. Those… “Who might rely on the
news for guidance, deserve
something more relevant”
(M. Blastland)

56. You can find me at:
www.clearpreso.com
www.twitter.com/clearpreso