between 30 and 87 with a mean age o

between 30 and 87 with a mean age of 64 years. The Swedish
student sample yielded 132 completed questionnaires. Of these,
ten were excluded due to lack of contact details, incomplete
questionnaires or lack of consent. Of the remaining 122 subjects 69
(56.6%) were female and 53 (43.4%) were male. The ages ranged
between 19 and 41 with a mean age of 23 years.
3.3. Validity of SEPI
3.3.1. SEPI part I
The correlation between each separate question in SEPI part I
and the corresponding questions in the Sun protective behaviour
questionnaire is shown in Table 1. Spearman’s Rho was calculated
in all four subpopulations (student population in Australia/
Sweden, PHC population in Australia/Sweden) as well as in the
total population in each country (Australia, Sweden). Correlation
coefficients showed satisfactory correlation for most of the
questions, with the exception of the SEPI question concerning
sun exposure on vacations, for which there was a negative
correlation with sunscreen use during vacation. The highest
coefficient values were seen forIntentional tanning, Occasions with
sunburnand Hat or cap for sun protection.
3.3.2. SEPI part II
In Table 2, the correlation between the questions in SEPI part II
and the related questions in the Sun protective behaviour
questionnaire, is displayed in the same manner as described
above for SEPI part I. Table 3 shows the median scores of SEPI part II
for each of the three stages of change (precontemplation,
contemplationandactionstage), respectively, based on which was
the dominant stage according to the responses in RASP-B. As seen
in the table, the median SEPI score was generally lower in the
action stage compared to the two other stages, whereas there was
no marked difference between the median scores in the
contemplation and precontemplation stages.
3.4. Reliability of SEPI
3.4.1. Internal consistency
In Tables 4a and 4b, the results of the Cronbach’s alpha analysis
for assessment of internal consistency, is presented. For SEPI part I,
the Cronbach’s alpha coefficient in the total populations ofAustralia
and Sweden were 0.69 and 0.61 respectively. For SEPI part II,
the corresponding outcomes were 0.67 in Australia and 0.57 in
Sweden. With deletion of the question on Sunscreen usein SEPI part
I, the Cronbach’s alpha increased to 0.71 in the Australian
population, and 0.73 in the Swedish population.
3.5. Test stability
3.5.1. Test stability
A test-retest analysed with Spearman’s Rho was also made
between both SEPI by matching the answers at baseline and at one
month’s follow-up, in order to evaluate test stability over time. The
Table 1
Correlation between the responses to the eight questions in SEPI part I and the one or more related question responses in the Sun-protective behaviours questionnaire (in
italics), assessed with Spearman’s Rho. Asterisks indicate statistical significance (* = P < 0.05, ** = P < 0.01).