ARTICLE
The majority of the prevention campaigns for skin cancer in the world
have been aimed at the early detection of tumours or at the identification
of precursor lesions. This has allowed the detection of more new cases
and resulted in a decrease in advanced cancers. Nonetheless, the incidence
of the three most frequent forms of skin cancer (melanoma, squamous cell
carcinoma and basal cell carcinoma) has considerably increased over the
last 20 years [1-4]. Moreover, the current epidemic is likely to be exacerbated
if the ongoing depletion of the ozone layer produces an increase in the
amount of environmental ultraviolet radiation on the earth's surface [5,
6], among other factors.
Taking into consideration that sunlight exposure is the main changeable
risk factor in skin cancer [7-9], we believe that primary prevention,
centred on education about skin cancer and sunlight protection is the
most appropriate way to control the incidence of skin cancer. The goal
should be to change incorrect habits and behaviour, leading in the short
term to a decrease in sunburning and in the long term to a fall in the
incidence of melanoma.
Children and teenagers are probably the groups most needing primary
prevention and most likely to benefit from it. They can receive up to
three times as much annual exposure to sunlight as adults, and it has
been calculated that 50 to 80% of a person's exposure to sunlight occurs
before the age of 18 to 21 [7, 8]. Furthermore, the use of UVA sunlamps,
particularly common in young women, and the high risk of melanoma associated
with a history of sunburn during childhood and adolescence seem to indicate
that school age is the ideal time for prevention campaigns. In addition,
it should be remembered that at this point in their lives, individuals
are more receptive to new information and to changes in their attitudes
and behaviour.
Numerous campaigns along these lines have been carried out, such as
the television and local newspaper "safe sun factors" in the USA, based
on the vigilance program of ultraviolet radiation from the National Meterological
Service [10]. In Australia programs for prevention and early detection
have been underway for more than 20 years. They have placed particular
emphasis on children, with informative campaigns in schools and the creation
of shaded areas in parks, pools and other public areas [11]. The American
Cancer Society has set up the program "Cancer prevention for children
in the USA" [12], where they are informed about drugs, alcohol, tobacco
and sunlight, encouraging positive attitudes. In Great Britain several
organizations and the media have begun to teach the general public about
the dangers of sunlight [13]. Information on melanoma has started to be
disseminated in Spain by the media, supported by the Spanish Academy of
Dermatology and Venereology (AEDV).
The present study has therefore been aimed at determining the awareness
and the behaviour of students in Granada city (Spain) with respect to
sunlight exposure as a basis for evaluating the need for and the designing
of a primary prevention campaign against skin cancer.
Granada lies in the province of the same name, forming part of the Autonomous
Community of Andalusia, in southern Spain. It is located between latitudes
38 05' and 36 42' north. The province has a varied geography, with 71
km of Mediterranean coast, but almost half of the area is above 1,000
m in altitude. This means that the inhabitants practise such diverse activities
as skiing and water sports in primarily sunny weather, with more than
3,000 hrs of sunlight annually. Granada city, the target of the survey,
has nearly a quarter of a million inhabitants.
According to the Granada cancer registry, skin cancer accounts for 20%
of the total cancer in both sexes. The second highest rate of spinal cellular
lip carcinomas in males are recorded here as well. Melanoma is among the
top three types of tumours with the highest incidence from 15 to 34 years
of age.
Materials and methods
A survey was designed to include the main points regarding the biological
effect of sunlight on the skin as well as the appropriate precautionary
measures. It was carried out during May 1996/1997 with 628 students from
12 to 14 years of age attending the first year of Secondary Education
at 9 different schools in Granada city. The schools, public, private,
and independent, were randomly selected to obtain a representative sample
of all the students in the town.
The survey was given to the students, with no forewarning, once they
were already in the classroom. The self-administered questionnaire consisted
of 3 parts. The first referred to general data such as name, school, age,
and sex. The second part comprised 15 true/false and yes/no responses
aimed at evaluating student awareness (Table
I). The third part also had 15 true/false and yes/no responses
for the purpose of determining behaviour (Table
II).
All the questionnaires were administered by the same researcher, who
gave only general instructions about filling out the survey, with the
aim of having identical survey conditions in all cases.
After the surveys were completed, the items were grouped into 4 sections
(Table III) for ease of
evaluation. Students were considered to have a good level of awareness
or good behaviour when they correctly answered half the points plus one,
for each section. We described the responses given by the student and
then statistically treated the answers using the chi2 test
and the Fisher precise test to evaluate the associations between each
of the sections and the gender of the students. We calculated the OR with
a confidence interval of 95% to determine the relationship between gender
and the different sections of questions. Girls constitute the reference
category. We searched for a significance of p < 0.05 in all the tests.
Results
Of the 628 students surveyed, 617 were white, two black and 9 gypsy.
The youngest was 11 years old and the oldest 16 (X: 12.6 0.63).
Most of the questions on awareness were satisfactorily answered by more
than 60% of the students, with the exception of 3 questions with a higher
percentage of wrong answers (Table
IV).
In the questions on Behaviour and Attitudes, it can be seen that more
than 60% (577) of those surveyed answered 9 questions wrong out of 13,
which signifies unhealthy attitudes and behaviour regarding sunlight exposure.
Analysis by sections shows a high ratio of right answers in the first
three sections regarding awareness (Sun and Skin, 79%; Sun and Environment,
86%; Sun and Health, 88%), but numerous wrong answers in the fourth section
on behaviour and attitudes (85% incorrect). Even when we lowered the acceptance
level for right answers in the last section, there were still 73% wrong
answers.
When the sections were cross-referenced for gender, there were seen
to be statistically significant relationships between Awareness of Sunlight
and Skin (p = 0.0001) and Attitudes and Behaviour (p = 0.0008). Boys show
less awareness of the relationship between sunlight and skin than girls
(OR = 0.42; IC 95% = 0.2-0.6). Girls also have better behaviour with respect
to sunlight exposure
(OR = 0.3; IC 95% = 0.2-0.6).
When each of the responses in Section I is cross-referenced to gender,
we find statistically significant relationships for the following points:
The sun can affect moles on the skin (p = 0.003).
Abundant sun ages the skin (p = 0.000001).
I have no chance of getting skin cancer because it only affects
older people (p = 0.00001).
The sun is good for the skin and therefore the more you get the
better (p = 0.01).
We conclude from the above that boys are unaware of the sun's influence
in pigmented lesions (OR = 0.5; IC 95% = 0.3-0.8), do not associate the
sun with aging of the skin (OR = 0.35; IC 95% = 0.25-0.50), claim that
skin cancer is an adult's disease (OR = 0.24; IC 95% = 0.09-0.6), and
consider an excess of sun to be good for the skin (OR = 0.3; IC 95% =
0.1-0.8).
We also studied the relationship between each of the responses in Section
IV (Attitudes and Behaviour) and gender, finding statistically significant
associations in the following items:
Do you take precautionary measures for sunlight exposure at the
beach or in the mountains? (p = 0.006);
Do you usually take precautionary measures on cloudy days at
the beach? (p = 0.04).
Having a swim to cool myself off and then continuing to enjoy
myself is an appropriate means of protection from the sun (p = 0.003).
This comparison reveals that girls take more precautions than boys at
the beach and in the mountains (OR = 1.8; IC 95% = 1.1-2.8) and on cloudy
days (OR = 0.7; IC 95% = 0.4-0.99). Boys believe that swimming is a good
protection against sunlight (OR = 0.6; IC 95% = 0.4-0.8).
Most of the students (58%) had never recommended the use of a sunscreen.
The analysis of this question is highly biased as well, since many students
left it blank as they did not know what a sunscreen was.
In Sections II and III (Relationship Sun and Environment and Relationship
Sun and Health) we found no statistically significant relationship with
gender. Nevertheless, when analysing the relationships of each of the
responses in these sections, it is interesting to note that, when asked
about the best time to sunbathe (p = 0.000001), boys stated that the best
hours were from 12 noon to 6 pm (OR = 0.4; IC 95% = 0.3-0.6).
Table V summarizes the
most significant results of the study.
Discussion and conclusions
As in the present study, most health education programs aimed at children
and teenagers choose the school as the best place to give the survey [14-16].
Some papers report that this is a difficult site since these types of
activities should not take up too much school time so as not to detract
from other pedagogical goals. Moreover, they claim that these surveys
can demand considerable training for the teachers or be so expensive that
the high training costs for teachers can create a discriminatory situation
in less-favoured school districts. In our work this situation did not
arise, since both the design and the administration of the survey was
carried out by members of our research team. In addition, we chose schools
to represent all the social levels in the city and kept to a schedule
agreed on with the schools'administrators.
Our results coincide with those of many other studies [17-24] that have
reported that children and teenagers are relatively unaware of the hazards
of sunlight exposure. Quite the contrary, they show nearly obsessive tendencies
to get a tan and reveal a great lack of protection to ultraviolet light,
whether from the sun or artificial sources. This kind of behaviour has
been described even among those with a higher risk due to a family history
of skin cancer or fair skin [17-24].
Recent investigation indicates that the general
public has a good awareness of sunlight exposure [17, 25-27], although
the relationship of this knowledge with behaviour is inconsistent [18,
19, 25, 28]. The same situation occurs with children and teenagers as,
for example, in the study by Cockburn et al. [19], where 70% of
the teenagers sampled used no sunscreen and awareness regarding skin cancer
was not associated with greater sunlight protection. The American Academy
of Dermatology carried out a national telephone survey that showed that
most adolescents could state at least one negative effect of the sun and
that 67% claimed to take precautions when exposed to sunlight radiation
[17]. Notwithstanding, almost 100% of the teenagers admitted that they
tanned voluntarily.
We fully concur with the results obtained in most studies, particularly
in the lack of association between the amount of awareness and the behaviour
followed. Another study in Northern Spain also revealed a better level
of awareness in girls than in boys [29]. This difference has also been
reported by the American Academy of Dermatology, where 66% of the girls
voluntarily tan, in spite of being conscious of the risk, compared to
34% of teenage boys.
Melbourne (Australia) [30] has been the site of similar surveys that
have shown a good level of awareness as well. However, despite the primary
prevention campaigns directed at the general public for more than 20 years,
the famous Slip, Slap, Slop [31] campaign did not achieve any changes
in the behaviour of the most needy sector, teenagers. Subsequently, they
therefore designed a campaign specifically for this group [11] in view
of the necessity for it and the great difficulty evident in producing
changes in behaviour.
It therefore seems obvious that campaigns for the prevention of skin
cancer must be directed specifically at behaviour modification. Since
this process is difficult and complex, it is not unlikely that most people
will be unwilling to change their sunlight exposure habits in order to
reduce the risk of skin cancer. What is more, resistance to adopting protective
behaviour continues to be strong [28, 32].
Given that mortality to skin cancer is quite low and that it is also
seen as belonging to a distant future, warnings about it may not be convincing
for many individuals. This is particularly true of teenagers, with their
whole life ahead of them and in whom interest in external appearances
and the perception of a tan as an indicator of good health are sufficiently
strong motivators for them to try to tan and ignore warnings concerning
skin cancer [16, 21, 33].
The best strategy may therefore be to emphasize the risk of cancer less
and insist on the short-term drawbacks related to physical appearance.
A certain amount of success has also been seen with the use of opinion
leaders, the example of parents, its inclusion in camp programs and/or
sports instructors [34-38].
Therefore, attempts to modify behaviour are undoubtedly the best approach
in the design of campaigns for the prevention of skin cancer.
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