Owen Carter Research Fellow Centre for Behavioural Research in Cancer Control Curtin University of Technology Assessing Western Australians’ Knowledge.

Owen CarterOwen CarterResearch FellowResearch Fellow

Centre for Behavioural Research in Cancer Centre for Behavioural Research in Cancer ControlControl

Curtin University of TechnologyCurtin University of Technology

Assessing Western Australians’ Knowledge of

the UV Index

Research funded by

• Primary cause UV radiation exposure

• Australia highest incidence in World

• Most common cancer 16-44 years

Skin Cancer

The Ultraviolet Index

• Standardised in 1995

• Forecast in Australia since 1996

Reporting of the UV Index

• Television• Newspapers• Internet• Radio

Awareness of the UV Index

90%(Blunden et al., 2004)

89%(Alberink et al., 2000)

64%(Kricker & Armstrong, 1998)

78%(White et al., 1997)

Use of the UV Index

37%

Knowledge of the UV Index

“Western Australians have a good level of

general knowledge about the (UV) Index”

Blunden et al. (2004)

Intensity of sun51%

Peak sun strength

14%

Intensity of sun51%

Amount of sunburn

18%

Sun protection required

3%

Risk of skin cancer

2%

Likelihood of sunburn

12%

Peak sun strength

14%

Accurate definitions65%

Knowledge of the UV Index

Blunden et al. (2004) – “All associate UVI with sun protection”

Amount of sunburn

18%

Sun protection required

3%

Risk of skin cancer

2%

Likelihood of sunburn

12%

Erroneous definitions

35%

88%31%

Knowledge of the UV Index

Solar noon12:00PM to 12:20PM

“Large majority aware that UV peaks at solar

noon”

Blunden et al. (2004) – Solar Noon

Knowledge of the UV Index

20%

20%

20%

20%

20%

“Is a UV Index score of 7 considered to beextreme, very high, high, moderate or low?”

12% correct

Blunden et al. (2004) – UVI Categories

“good level”of general knowledge…

• Intercept interviews

Study Methodology

• Six stratified focus groups

N=2,020

Not heard of UVI9%

Not sunburnt6%

Non-English speaking

5%

Non-Perth residents

19%

Refusals41%

Final sample20%

Final sample20%

• N=404 (201 males and 203 females)• Average age of 29.4 years (range 16–44)

– All residents of Perth– All aware of UVI– All sunburnt in last year (1-90 times)

0%

5%

10%

15%

20%

25%

1 2 3 4 5 6 7 8 9 10 11 12 13+

Median = 3

Intercept Interview Sample

Forecast RecallWhat was the forecast today for the UV Index?

46.3%

18.6%

32.9%

5.2%0.5% 1.0%

0%

10%

20%

30%

40%

50%

60%

Claimedknowledge

CorrectResponse

Approximatelycorrect (± 1)

TemperatureUVI

0

2

4

6

8

10

12

14

UV

Ind

ex

Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun

34

6

8

1011

1211

9

6

43

Knowledge of UVI rangesWhat is the average UVI in Perth during summer/winter?

UVI= UVI=1

0%

10%

20%

30%

40%

0-5 6-10 11-15 16-20 21-25 26-30 31-35 36+

Summer

Winter

239 3+6 +1

Perth UVI Monthly Averages

Winter Summer

SPF 30+

True or False?

True or False?True or False?

True or False?

True or False?

True or False?True or False?

True or False?True or False?

True or False?Small

Very Hot

DangerousMedium

Extremely High

Low

Moderate

ExtremeVery High

High90%

0% 25% 50% 75% 100%

Recognition of UVI categories

UVI category

Decoy

State which of the following are associated with the UV Index?

9%

14%

24%

52%

58%

84%

82%

88%

94%

88% 31%

t(383)=39.425 p<.001

True or False?

True or False?True or False?

True or False?

True or False?

True or False?True or False?

True or False?True or False?

True of False?Small

Very Hot

DangerousMedium

Extremely High

Low

Moderate

ExtremeVery High

High

Confusion with Burn-timeIs it true or false that the UV Index tells you how many minutes it

will take to get sunburnt?

Don't know2%

15%False83%77%

True23%

22-44 years

χ2(1)=10.310 p<.01

Association with Temperature

Is the UVI dependent or independent

on the temperature?

Don't know13%

Dependent48%

Independent39%

61%

Ignorant of independence

Binomal test [50%] p<.05

Same5%

Don’t know2%

3:00 PM48%

11:00 AM45%

Role of Solar NoonAre UV conditions more intense at 11AM or 3PM?

Same5%

Don’t know2%

3:00 PM48%

11:00 AM45%

Unaware of Solar Noon≥55%

Aware of Solar Noon≤45%

88%

high

extreme

Binomal test [50%] p<.05

0%

10%

20%

30%

40%

50%

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21+

UVI under cloud

UVI and Cloud CoverIf the UV clear-sky forecast was 12

what might it be under moderate cloud cover?

43%

13%

7%43%

UV INDEX: 12[EXTREME] decreasing to 8[VERY HIGH] under cloud

Conclusions

• High awareness of the UVI and its category labels

• Basic appreciation

• Widespread misconceptions regarding– variation– temperature– cloud cover

Where to from here• Bell-curve concept