Patterns of Sun Protection Behaviours among Australian Adolescents and Adults over a Six-Year Period

Abstract

The major cause for skin cancer is the excessive and unprotected exposure to ultraviolet radiation (UVR), which can be prevented by engaging in sun protection behaviours. As longitudinal studies on both adolescents’ and adults’ performances of sun protection behaviours are limited, the current study aimed to investigate changes in sun protection in these population segments in Western Australia, a region with high annual UVR. During six summer seasons (2015/16 to 2020/21), cross-sectional surveys were conducted among 1806 adolescents (14 to 17 years old) and 1808 adults (18–45 years old), investigating the frequency of five sun protection behaviours (wearing clothing, applying sunscreen, wearing a hat, wearing sunglasses, and seeking shade) and sun avoidance (staying indoors). Over the six-year period, staying indoors increased in both groups. Among adolescents, a decrease in wearing clothing and sunglasses and an increase in seeking shade was demonstrated, and hat and sunscreen use remained relatively stable. Among adults, an increase in sunscreen use was shown, whereas all other sun-related behaviours remained consistent over the six-year period. The results from this study can provide directions for health communications focusing on improving sun protection behaviours among both adolescent and adult populations.

Full text

Citation: Thoonen, K.; Woodhouse,
S.; Minto, C.; Blane, S.; Talati, Z.
Patterns of Sun Protection Behaviours
among Australian Adolescents and
Adults over a Six-Year Period. Curr.
Oncol. 2023,30, 7178–7188. https://
doi.org/10.3390/curroncol30080520
Received: 25 June 2023
Revised: 17 July 2023
Accepted: 21 July 2023
Published: 26 July 2023
Copyright: © 2023 by the authors.
Licensee MDPI, Basel, Switzerland.
This article is an open access article
distributed under the terms and
conditions of the Creative Commons
Attribution (CC BY) license (https://
creativecommons.org/licenses/by/
4.0/).
Article
Patterns of Sun Protection Behaviours among Australian
Adolescents and Adults over a Six-Year Period
Karlijn Thoonen 1, Sade Woodhouse 2, Carolyn Minto 3,*, Sally Blane 3and Zenobia Talati 2
1Melbourne Centre for Behaviour Change, Melbourne School of Psychological Sciences, The University of
Melbourne, Melbourne 3010, Australia
2School of Population Health, Curtin University, Perth 6845, Australia; zenobia.talati@curtin.edu.au (Z.T.)
3Cancer Council Western Australia, Perth 6008, Australia; sally.blane@cancerwa.asn.au
*Correspondence: carolyn.minto@cancerwa.asn.au
Abstract:
The major cause for skin cancer is the excessive and unprotected exposure to ultraviolet
radiation (UVR), which can be prevented by engaging in sun protection behaviours. As longitudinal
studies on both adolescents’ and adults’ performances of sun protection behaviours are limited,
the current study aimed to investigate changes in sun protection in these population segments in
Western Australia, a region with high annual UVR. During six summer seasons (2015/16 to 2020/21),
cross-sectional surveys were conducted among 1806 adolescents (14 to 17 years old) and 1808 adults
(18–45 years old), investigating the frequency of five sun protection behaviours (wearing clothing,
applying sunscreen, wearing a hat, wearing sunglasses, and seeking shade) and sun avoidance
(staying indoors). Over the six-year period, staying indoors increased in both groups. Among
adolescents, a decrease in wearing clothing and sunglasses and an increase in seeking shade was
demonstrated, and hat and sunscreen use remained relatively stable. Among adults, an increase
in sunscreen use was shown, whereas all other sun-related behaviours remained consistent over
the six-year period. The results from this study can provide directions for health communications
focusing on improving sun protection behaviours among both adolescent and adult populations.
Keywords: skin cancer prevention; sun protection; adolescents; repeated cross-sectional design
1. Introduction
Skin cancer, consisting of melanoma and non-melanoma skin cancer (NMSC) is the
most common cancer globally, and incidence rates have been increasing rapidly over the
last several decades [
1
,
2
]. Australia is among the countries with the highest incidence, and
it has been predicted that two-thirds of Australians will be diagnosed with skin cancer
during their lives [
3
]. Early detection and treatment are costly to the Australian health
system, with a healthcare expenditure of over AUD 259 million for melanoma and AUD
1.46 billion on NMSC in 2019 [4].
Risk factors for skin cancer include unprotected exposure to ultraviolet radiation
(UVR), a history of several sunburns, and sensitive skin [
5
,
6
]. Therefore, skin cancer is
considered a highly preventable malignancy [
7
,
8
]. Recommended sun safety strategies
to protect the skin consist of five behaviours (i.e., wearing protective clothing, a wide-
brimmed hat, and sunglasses, applying sunscreen with a sun protection factor (SPF) of
>30, and seeking shade [
9
–
11
]). Additionally, staying indoors during peak UVR hours has
been measured as a sun-avoidance strategy [
12
]. These prevention efforts are especially
important in Western Australia (WA), where UVR levels reach 11 on average during
summer [13].
Sun protection during childhood and adolescence have been marked as particularly
important since skin damage in these stages of life are strongly related to skin cancer risk
in adulthood [
14
,
15
]. Although important, studies have revealed that adolescents’ sun
protection behaviours are generally poor [
16
,
17
]. From an Australian perspective, research
Curr. Oncol. 2023,30, 7178–7188. https://doi.org/10.3390/curroncol30080520 https://www.mdpi.com/journal/curroncol

Curr. Oncol. 2023,30 7179
has shown that sun protection strategies in adolescents seem to be inconsistent. For example,
hat use has been reported less frequently in the last three decades, whereas wearing clothing
and sunscreen appeared to remain relatively stable [
18
,
19
]. Sunglasses were frequently
worn from 2006 to 2008 but returned to the baseline levels in 2012 and continued to
decline in 2016 [
18
]. Sun avoidance seemed to increase from the early 2000s [
18
,
20
,
21
].
Additionally, sunburn incidence seemed to be consistently prevalent, with between 21 and
25% of adolescents in the area of Melbourne reporting a sunburn during summer between
2003-04 and 2016-17 [21–23].
Patterns in sun protection behaviours among Australian adults have yielded more
positive results. For example, studies from Melbourne showed that the use of sunscreen
along with one or more other methods of sun protection increased between the late 1980s
and 2010s. This resulted in a decrease in the proportion of unprotected skin until the late
1990s, and rates of sunburn declined until 2002 [
24
,
25
]. Nevertheless, inconsistencies were
also observed. For example, findings of wearing protective clothing were inconsistent across
studies [
12
,
20
] and hat wearing seemed to decrease between the summer season of 2003/04
and 2010/11 [
21
]. A recent observational study reported that older adults and women
consistently performed sun protection behaviours more frequently than adolescents and
younger adults [
26
]. These fluctuations highlight that sun protection behaviours are prone
to change and that public health efforts are needed continuously and systematically [
25
,
27
].
Adolescence marks an important developmental phase in which normative beliefs
are changing and shifts take place from parental impact towards peer influences [
11
].
Self-consciousness and the internalisation of norms and values increase, making it a
crucial period for the formation of habitual behaviours [
28
,
29
]. From a sun protection
perspective, studies have demonstrated that the transitioning phase from childhood to
adolescence is especially important for independently learning and performing sun safety
strategies [
17
,
30
]. Moreover, appearance-based norms become more important in adoles-
cence, including the desire for a tan and tanning behaviours [
31
–
33
], and sun protection
attitudes seem to decline [16].
Australia has established skin-cancer-prevention efforts that have been ongoing for
decades, consisting of various public health interventions focusing on improving skin can-
cer knowledge and sun safety behaviours on both a state and national level [
27
]. The most
widely recognised is Cancer Council Victoria’s major skin-cancer-prevention campaign
‘Slip, Slop, Slap’, that was first broadcasted in the 1980s [
34
]. The campaign’s effects had
long-lasting success, with a dramatic improvement seen in Australian adults’ sun protec-
tion behaviours up until the early 2000s [
20
,
24
]. Besides individually focused successes,
policy and institutional changes were also established [27].
By updating current knowledge on sun protection behaviours of two important popu-
lation segments, directions for improvement and tailored content for skin-cancer-prevention
efforts can potentially be provided. As previously repeated cross-sectional survey studies
between 2001 and 2016 demonstrated little to no improvement in adolescent sun-related
behaviours while adult behaviours seemed to remain relatively stable [
12
,
18
,
20
], this study
aimed to gain insight in Western Australian adolescent and adult sun-related behaviours
over a more recent six-year period (2015/16 and 2020/21).
2. Materials and Methods
2.1. Participants and Recruitment
A telephone-based survey study was conducted among adolescents and adults, using
a repeated cross-sectional design over six summer waves (2015/16–2020/21). This study
was part of a larger sun protection monitoring and campaign evaluation study of Cancer
Council WA. Of interest for this study were adolescents aged between 14 and 17 and adults
aged between 18 and 45, residing in WA. In total, 3614 respondents answered a telephone
survey, consisting of 1806 adolescents and 1808 adults.
Quotas were set each year to recruit approximately 300 respondents and ensure the
sample consisted of 50% males and 50% females, and 50% adolescents and 50% adults.

Curr. Oncol. 2023,30 7180
Quotas were also set by location with the aim of recruiting 30% regional residents. From
2015/16–2017/18 the Electronic White Pages database was used for randomly selecting and
calling households in WA, and from 2018/19 onward, the Australian Residential Database
was used. All data collection took place during January and February (Australian peak
summer). Table 1shows the key sample demographics.
Table 1. Sample demographics (N = 3614).
Characteristic Adolescents
n= 1806
Adults
n= 1808
n%n%
Age
14–15 885 49.0
16–17 921 51.0
18–24 606 33.5
25–35 606 33.5
36–45 596 33.0
Gender
Male 906 50.2 903 49.9
Female 900 49.8 905 50.1
Skin colour
Very fair 222 12.3 264 14.6
Fair 591 32.7 641 35.5
Medium 501 27.7 489 27.0
Olive 363 20.1 344 19.0
Dark 101 5.6 61 3.4
Very dark 11 0.6 5 0.3
Black 17 0.9 4 0.2
Location
Metropolitan 1277 70.7 1245 68.9
Regional 529 29.3 563 31.1
2.2. Measures
A sun protection survey was administered via computer-assisted telephone interview-
ing (CATI) to assess respondents’ attitudes towards being outside in the sun and their
engagement in six sun-related behaviours. Demographic characteristics were assessed by
asking about respondents’ age (open question), gender (1 = male, 2 = female), skin type,
by asking about the skin colour without a tan (1. very fair, 2. fair, 3. medium, 4. olive,
5. dark, 6. very dark, 7. black, 8. don’t know/can’t say), and area of residency by asking
respondents about their postcode and suburb. Five behaviours comprised outdoor sun
protection behaviours (wearing protective clothing, wearing sunscreen, wearing a wide-
brimmed hat, wearing sunglasses, and seeking shade), and the sixth concerned total sun
avoidance (staying indoors). Respondents were asked to indicate how often they would
engage in the sun-related behaviours when being outside on a summer day for more than
one hour between peak UV hours (between 10 a.m. and 3 p.m.) on a 5-point Likert scale
(1 = never, 2 = rarely, 3 = sometimes, 4 = usually, 5 = always).
2.3. Procedure
This study was approved by a University Human Ethics Committee. Potentially
eligible households were approached by telephone, after which a trained interviewer
asked whether they could speak to a household member aged between 14 and 45 years
and explained the study’s interest in attitudes about the sun protection of WA residents.
Most survey items were based on a structured interview guide with fixed responses for
the interviewer to choose from. After finalising the survey, the interviewer thanked the
respondent and provided their name, affiliation, and contact information for the respondent

Curr. Oncol. 2023,30 7181
to use when questions would arise. Households without members aged between 14 and
45 were recorded as ineligible. Informed consent was obtained when a respondent agreed
to continue with the survey. Parental consent was required for minors (aged < 16 years)
to participate.
2.4. Statistical Analyses
Descriptive statistics were computed to explore the data and verify normal distribution
of gender and age. No missing values were present except for ‘Don’t know/Can’t say’
responses on the skin type question, that were treated as missing values.
The dependent variables consisted of composite scores of five reported sun protection
behaviours and sun avoidance, and the independent variables consisted of the survey
year. Pearson’s chi-squared tests of independence were performed to compare the mean re-
sponses for each sun-related behaviour per survey year, stratified by age group (adolescent
or adult) [
35
]. Post hoc Z-tests of proportion with Bonferroni correction were conducted
to identify significant differences [
36
]. Based on these results, one hierarchical linear re-
gression analysis per age group was performed to test for associations between survey
year and sample means of six sun-related behaviours, after controlling for demographic
variables (i.e., age, gender, skin type, and area of residency). Effect sizes were examined
using Cramer’s V (
ϕ
), considering Cohen’s suggestion of effect sizes (i.e., 0.10 = small,
0.30 = medium, and 0.50 = large) [
37
,
38
]. An alpha level of p< 0.05 was predefined to
determine statistical significance. All data analyses were performed using IBM SPSS Statistics.
3. Results
Information on all frequencies of engagement in sun-related behaviours of adolescents
and adults per survey year can be found in Table 2. Consider Table 3for sample means
stratified by survey year and age group.
3.1. Adolescents
Wearing sunscreen was the most frequently reported sun protection behaviour in
adolescents across all survey years (M = 3.65), followed by seeking shade (M = 3.39), and
hat wearing (M = 3.04). Adolescents most often reported wearing protective clothing
rarely to sometimes (M = 2.80). Wearing sunglasses was the least frequently reported sun
protection method across all survey years (M = 2.64).
The proportion of adolescents that reported ‘rarely’ wearing protective clothing in-
creased by almost 90% from 2015/2016 to 2020/21, and the number of respondents that
stated ‘always’ wearing protective clothing decreased by more than 60% from 2015/16 to
2018/19. Adolescents who reported that they ‘rarely’ sought shade decreased by almost
60% between 2018/19 and 2019/20. The proportion of adolescents that reported to ‘never’
wear sunglasses increased by almost 66% between 2017/18 and 2020/21. Adolescents that
reported ‘never’ for staying indoors decreased from 2016 and all subsequent years, and
the proportion of respondents reporting that they ‘usually’ stay inside increased by almost
41% from 2016/17 to 2020/21. Small associations were found between survey year and
the frequency of wearing protective clothing (
ϕ
= 0.18), seeking shade (
ϕ
= 0.14), wearing
sunglasses (ϕ= 0.20), and staying indoors (ϕ= 0.18).
Results from the linear regressions to determine predicting factors for engaging in sun-
related behaviours are presented in Table 4. In the first model where survey year was not
included, skin type was negatively associated with the frequency of reported sun-related
behaviours (p< 0.001). When adding survey year and controlling for age, gender, skin type,
and area of residency, results showed that skin type was the only significant remaining
factor explaining the variance in outdoor sun protection behaviours (p< 0.001).

Curr. Oncol. 2023,30 7182
Table 2. Frequencies of engagement in sun-related behaviours per survey year for adolescents and adults.
Variables
Survey Year
2015/16 2016/17 2017/18 2018/19 2019/20 2020/21
Wear protective clothing Adolescents Adults Adolescents Adults Adolescents Adults Adolescents Adults Adolescents Adults Adolescents Adults
% Never 17.4 20.6 15.2 14.7 14.2 12.3 14.4 14.6 17.0 21.6 12.8 17.5
% Rarely 16.0 20.6 26.5 23.1 25.8 21.5 26.0 19.9 35.0 16.6 31.2 24.1
% Sometimes 31.8 26.6 31.5 23.7 32.1 30.5 26.8 27.5 22.6 25.9 24.8 22.1
% Usually 24.6 22.9 20.2 28.4 21.9 26.8 28.8 28.8 18.7 25.6 22.8 23.4
% Always 10.2 9.3 6.6 10.0 6.0 8.9 4.0 9.2 6.7 10.3 8.4 12.9
Wear sunscreen Adolescents Adults Adolescents Adults Adolescents Adults Adolescents Adults Adolescents Adults Adolescents Adults
% Never 9.5 12.6 7.9 6.7 4.6 4.0 7.4 8.3 6.3 8.6 8.0 9.6
% Rarely 12.4 11.6 9.6 9.7 8.9 6.0 8.0 10.6 9.3 6.0 9.7 9.2
% Sometimes 22.0 19.6 22.8 12.4 19.2 20.5 21.4 15.9 23.0 18.6 21.8 17.8
% Usually 35.1 28.2 33.8 29.4 30.5 30.4 32.1 24.5 36.7 30.9 32.6 28.1
% Always 21.0 27.9 25.8 41.8 36.8 39.1 31.1 40.7 24.7 35.9 27.9 35.3
Wear a hat Adolescents Adults Adolescents Adults Adolescents Adults Adolescents Adults Adolescents Adults Adolescents Adults
% Never 19.0 19.9 15.6 19.0 12.6 11.2 16.0 12.9 17.0 12.9 16.1 13.5
% Rarely 17.7 10.6 18.5 7.4 16.2 12.6 12.4 13.5 20.0 11.0 20.8 12.5
% Sometimes 28.2 17.6 25.2 17.4 27.2 13.9 28.4 17.5 26.7 17.6 24.2 13.2
% Usually 20.0 24.3 26.5 25.8 30.8 29.8 27.8 24.2 26.7 28.9 23.8 26.7
% Always 15.1 27.6 14.2 30.4 13.2 32.5 15.4 31.8 9.6 29.6 15.1 34.0
Wear sunglasses Adolescents Adults Adolescents Adults Adolescents Adults Adolescents Adults Adolescents Adults Adolescents Adults
% Never 33.1 8.6 27.8 9.4 24.1 5.6 31.1 8.3 35.0 9.0 40.6 9.2
% Rarely 17.7 4.3 14.9 3.3 19.9 3.6 16.0 4.6 22.0 5.6 23.8 7.3
% Sometimes 14.4 9.6 24.5 8.4 15.6 8.9 18.1 8.3 16.7 10.0 14.8 8.9
% Usually 16.1 19.9 19.5 17.0 19.2 19.9 15.4 15.9 14.3 14.6 11.4 19.1
% Always 18.7 57.5 13.2 61.9 21.2 61.9 19.4 62.9 12.0 60.8 9.4 55.4
Seeking shade Adolescents Adults Adolescents Adults Adolescents Adults Adolescents Adults Adolescents Adults Adolescents Adults
% Never 2.3 1.3 3.0 4.3 0.7 1.0 2.7 4.0 2.7 4.3 1.7 5.3
% Rarely 10.1 10.6 12.9 10.0 8.2 7.3 15.7 5.6 6.3 6.0 11.1 9.6
% Sometimes 36.1 30.9 42.4 34.1 46.4 31.1 36.8 33.8 38.3 32.2 36.2 30.3
% Usually 44.6 41.9 38.1 40.1 39.1 46.7 38.1 41.0 44.3 46.2 44.3 42.6
% Always 6.9 15.3 3.6 11.4 5.6 13.9 6.7 15.6 8.3 11.3 6.7 12.2
Stay indoors Adolescents Adults Adolescents Adults Adolescents Adults Adolescents Adults Adolescents Adults Adolescents Adults
% Never 3.3 4.0 5.0 7.3 2.0 2.6 1.0 2.6 0.7 1.7 0.7 3.6
% Rarely 12.1 11.6 16.9 15.4 16.9 13.6 11.0 8.6 13.0 7.3 11.4 8.9
% Sometimes 39.0 40.9 42.3 32.4 40.1 40.7 40.5 33.8 36.3 35.2 36.5 33.0
% Usually 36.1 37.5 30.8 36.5 38.7 37.1 43.1 45.0 44.3 49.2 44.0 46.5
% Always 9.5 6.0 5.0 8.4 2.3 6.0 4.3 9.9 5.7 6.6 7.4 7.9

Curr. Oncol. 2023,30 7183
Table 3. Sample means of sun-related behaviours per survey year for adolescents and adults.
Variables Survey Year
Adolescents (N= 1806) 2015/16 2016/17 2017/18 2018/19 2019/20 2020/21 χ2ϕ’
Wear protective clothing
Mean (SD) 2.94 (1.23) 2.76 (1.14) 2.79 (1.12) 2.82 (1.12) 2.63 (1.16) 2.83 (1.17) χ2(20) = 52.88 *** ϕ’ = 0.09 **
Wear sunscreen
Mean (SD) 3.46 (1.22) 3.60 (1.20) 3.86 (1.15) 3.72 (1.20) 3.64 (1.14) 3.62 (1.21) χ2(20) = 29.20 * ϕ’ = 0.06
Wear a hat
Mean (SD) 2.94 (1.32) 3.05 (1.28) 3.16 (1.22) 3.14 (1.28) 2.92 (1.24) 3.01 (1.30) χ2(20) = 26.57 * ϕ’ = 0.06
Wear sunglasses
Mean (SD) 2.70 (1.53) 2.75 (1.39) 2.93 (1.49) 2.76 (1.51) 2.46 (1.40) 2.25 (1.34) χ2(20) = 67.47 *** ϕ’ = 0.10 **
Seeking shade
Mean (SD) 3.44 (0.85) 3.26 (0.84) 3.41 (0.75) 3.30 (0.91) 3.49 (0.84) 3.43 (0.84) χ2(20) = 37.01 * ϕ’ = 0.07 *
Stay indoors
Mean (SD) 3.36 (0.93) 3.14 (0.93) 3.23 (0.83) 3.39 (0.78) 3.41 (0.81) 3.46 (0.82) χ2(20) = 58.92 *** ϕ’ = 0.09 **
Adults (N= 1808) 2015/16 2016/17 2017/18 2018/19 2019/20 2020/21 χ2ϕ’
Wear protective clothing
Mean (SD) 2.80 (1.26) 2.96 (1.23) 2.99 (1.16) 2.98 (1.20) 2.86 (1.30) 2.90 (1.30) χ2(20) = 28.74 * ϕ’ = 0.06
Wear sunscreen
Mean (SD) 3.47 (1.34) 3.90 (1.24) 3.95 (1.09) 3.79 (1.30) 3.79 (1.24) 3.70 (1.30) χ2(20) = 45.56 *** ϕ’ = 0.08 **
Wear a hat
Mean (SD) 3.29 (1.47) 3.41 (1.47) 3.60 (1.35) 3.48 (1.39) 3.51 (1.36) 3.55 (1.41) χ2(20) = 29.36 * ϕ’ = 0.06
Wear sunglasses
Mean (SD) 4.13 (1.27) 4.19 (1.28) 4.29 (1.13) 4.21 (1.27) 4.13 (1.32) 4.04 (1.33) χ2(20) = 17.26 * ϕ’ = 0.05
Seeking shade
Mean (SD) 3.59 (0.92) 3.44 (0.97) 3.65 (0.84) 3.59 (0.95) 3.54 (0.93) 3.47 (1.00) χ2(20) = 30.59 * ϕ’ = 0.07
Stay indoors
Mean (SD) 3.30 (0.90) 3.23 (1.05) 3.30 (0.87) 3.51 (0.88) 3.52 (0.79) 3.46 (0.90) χ2(20) = 52.23 *** ϕ’ = 0.09 **
Note: SD = Standard deviation; χ2= chi-squared test of independence; ϕ’ = effect size (Cramer’s V). * p< 0.05, ** p< 0.01, *** p< 0.001.

Curr. Oncol. 2023,30 7184
Table 4. Hierarchical linear regression results for adolescents and adults.
Adolescents
(N= 1806)
Adults
(N= 1808)
Variables B (95% CI) βsr2B (95% CI) βsr2
Step 1
Age 0.02 (−0.01, 0.04) 0.03 0.00 0.03 (0.02, 0.03) 0.29 *** 0.09
Gender 0.03 (−0.03, 0.09) 0.02 0.00 0.01 (−0.05, 0.07) 0.01 0.00
Location 0.04 (−0.02, 0.11) 0.03 0.00 0.07 (0.00, 0.14) 0.05 0.00
Skin type −0.11 (−0.14, −0.09) −0.21 *** 0.04 −0.12 (−0.14, −0.09) −0.18 *** 0.03
Step 2
Age 0.02 (−0.01, 0.04) 0.03 0.00 0.03 (0.02, 0.03) 0.29 *** 0.09
Gender 0.03 (−0.03, 0.08) 0.02 0.00 0.01 (−0.05, 0.07) 0.01 0.00
Location 0.04 (−0.02, 0.11) 0.03 0.00 0.07 (0.00, 0.14) 0.05 0.00
Skin type −0.11 (−0.14, −0.09) −0.21 *** 0.04 −0.12 (−0.14, −0.09) −0.18 *** 0.03
Year −0.02 (−0.03, 0.00) −0.04 0.00 0.01 (−0.01, 0.02) 0.01 0.00
Note. CI = Confidence interval. *** p< 0.001.
3.2. Adults
Adults reported wearing sunglasses most often across all survey years (M = 4.17),
followed by using sunscreen (M = 3.77). The least reported sun protection behaviour was
wearing protective clothing (M = 2.92).
The proportion of adults that reported to ‘never’ wear sunscreen decreased by 68.4%
between 2015/16 and 2017/18, and ‘always’ wearing sunscreen was reported more fre-
quently in 2016/17 and 2018/19 compared to other survey years. The proportion of adults
that reported to ‘never’ stay inside decreased by 77.3% from 2016/17 to 2019/20, and ‘rarely’
staying inside was reported 52.2% less often from 2016/17 to 2019/2020. Associations
between survey year and the frequency of using sunscreen and staying indoors were found
(ϕ= 0.16 and ϕ= 0.18, respectively).
In the first regression model, the predictive values for age, gender, skin type, and area
of residency were tested. The results showed that age was positively associated (p< 0.001)
and skin type was negatively associated (p< 0.001) with the frequency of reported sun
protection behaviours. When controlling for age, gender, skin type, and area of residency in
the second model, age (p< 0.001) and skin type (p< 0.001) remained significantly associated
with adult sun protection behaviours. These results can be found in Table 4.
4. Discussion
This study examined the reported performance of recommended sun protection strate-
gies by Australian adolescents and adults over six summers (2015/16 to 2020/21). The
insights provided through these observations could potentially assist directing future
skin-cancer-prevention campaigns. The findings indicated that adolescent sun protection
behaviours are suboptimal and have not improved during the study period. Extending on a
previous study among WA adolescents, most behaviours remained relatively consistent [
18
].
Adults seemed to perform sun protection strategies regularly and their behaviours show a
relative consistency throughout the six-year period, which is comparable to the behaviours
reported over an earlier time period [12].
The finding that adolescents seem to engage less in sun protection behaviours than
adults replicate other studies conducted in Australia [
23
], as well as in the United States [
31
],
Germany [
38
], and Ireland [
39
]. More specifically, the least performed and declining sun
protection behaviour among adolescents was wearing sunglasses. This result extends
previous cross-sectional research in Australia, reporting an increase in adolescent sunglasses
usage from 2001/02 to 2010/11 with a steep drop in 2012 [
18
]. Another study from Australia
found a decrease in sunglasses use among adolescents as well [
20
]. This is significant given
that 50% of total UV exposure up to age 60 occurs before age 20 [
40
], making adolescence a
critical period for determining future skin cancer and eye damage risk. More specifically,

Curr. Oncol. 2023,30 7185
young people are particularly vulnerable to UVR because they have larger pupils and
more transparent ocular media, making the use of eye protection from an early age of
considerable importance [41].
Previous research among adolescents suggested that the desirability of a tan, having a
non-favourable attitude about sun protection and a strong influence of fashion trends on
wearing protective garments might explain poor sun protection compliance [
42
–
44
]. More-
over, an absence of long-term risk perceptions regarding skin cancer and a future quality
of life among adolescents might function as a barrier for sun protection performance [
45
].
An Australian study aimed at understanding adolescent sun protection attitudes and be-
haviours found several misperceptions (e.g., about the risks of unprotected sun exposure
and when to apply sunscreen) and a strong desire for a tanned skin, which persisted
when adolescents were aware of the health-risks involved [
46
]. As several determinants
(e.g., skin cancer knowledge, skin cancer risk perceptions, sun protection attitudes) and
sun-exposure habits influence actual sun protection behaviours, it could be relevant to
further investigate this relation among these population segments as well [
20
,
42
,
46
]. Based
on the findings from this study, it may be worth further exploring emotions evoking skin-
cancer-prevention campaigns as this could be a potential facilitator for positive change.
For example, emphasising more immediate outcomes instead of long-term risks such as
avoiding sunburn as a motivator for sun protection instead of decreasing skin cancer risk
might be beneficial [45,46].
Wearing protective clothing was the second lowest reported sun protection method
among adolescents and the least popular behaviour among adults, which is concerning.
Covering the skin with clothing has been proposed as an important sun protection strategy
and might potentially be more effective than hat-wearing or sunscreen use in preventing
skin damage [
23
,
47
–
49
]. Since clothing is subject to changes in fashion and protective
clothing might be perceived as uncomfortable or inconvenient, demonstrations of role
models that are covering up with comfortable and wearable clothing might be effective
in sun protection campaigns [
49
–
51
]. Furthermore, sun avoidance increased among both
adolescents and adults. While staying indoors is favourable since it may reduce skin cancer
risk, it is debatable whether this is a favourable tendency considering the increase in screen
time that has been observed among Australian children and adolescents since 2012, which
has been associated with less engagement in physical activity [52].
Mobile apps may provide an effective strategy for disseminating tailored sun protec-
tion messages to adolescents [
53
,
54
]. Moreover, social media sites such as Twitter have the
potential to send health communications to large population groups, and adolescents seem
to intentionally use social media for seeking specific health information [
55
,
56
]. An Aus-
tralian study has shown that Twitter is being used for sharing sun protection experiences
and advice, especially during days with high temperatures [
57
]. Utilising social media for
prompting the use of sun protection could potentially be an effective strategy for enhancing
adolescent sun protection behaviours.
5. Limitations
There are a few limitations in this study that are worth mentioning. First, this study
used a repeated cross-sectional study design, meaning that each time point included a
different sample of respondents and that the findings represent changes at a population
rather than an individual level [58]. Second, this study relied on self-reported behaviours,
allowing for the possibility of a recall bias and respondents providing socially desirable
answers [
59
,
60
]. To minimise this, outliers in the data were carefully examined and standard
deviations and confidence intervals were reported. Third, self-reported sunscreen use has
shown to correspond with objective sunscreen use in previous research [
59
]. Finally, this
study did not assess factors that may relate to or influence sun-related behaviours (e.g., sun
exposure, prior sun protection knowledge and exposure to sun safety interventions). Future
studies should ideally include these factors to investigate the underlying components of
engagement in sun protection behaviours.

Curr. Oncol. 2023,30 7186
6. Conclusions
This study aimed to examine changes in sun-related behaviours of both adolescents
and adults in Western Australia over a six-year period (2015/16 to 2020/21). Adolescents
reported engaging less in sun protection behaviours than adults, and decreases were found
in wearing sunglasses among adolescents. Wearing protective clothing was among the least
reported behaviours of both adolescents and adults. Staying indoors increased over the six-
year period among both groups. The findings from this study contribute to current insights
of adult and adolescent sun-related behaviours and can potentially assist in shaping future
health communications by tailoring message content.
Author Contributions:
K.T.: Methodology, Writing—original draft, Writing—review and editing,
Supervision. S.W.: Formal analysis, Data curation, Writing—original draft. C.M.: Funding acqui-
sition, Conceptualization, Writing—review and editing, Supervision. S.B.: Funding acquisition,
Conceptualization, Supervision. Z.T.: Conceptualization, Methodology, Writing—review and editing,
Supervision, Project administration. All authors have read and agreed to the published version of
the manuscript.
Funding:
The Western Australian Health Promotion Foundation (Healthway) and the Western Aus-
tralian Department of Health funded the implementation and evaluation of the SunSmart advertising
campaign, which is the source of the data used in this study.
Institutional Review Board Statement:
This project was approved by the Curtin University Ethics
Committee (RD-19-14-1), Western Australia, on 13 June 2022.
Informed Consent Statement:
Informed consent was obtained from all subjects involved in the
study. Since telephone surveys were conducted, consent was obtained verbally prior to commencing
the interviews.
Data Availability Statement: Data can be made available upon request.
Conflicts of Interest:
The authors declared no potential conflict of interest with respect to the research,
authorship, and/or publication of this article.
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