Table 2. Mean changes of score between the three follow-up occasions (baseline, 3 years, and 10 years), regarding sun habits and sun protection behaviour, and the statistical significance according to the overall effect of time, group, and a combination of both
Model results
Change in estimated marginal meansTests of fixed effects, P value
LetterDoctor's consultationPhototest
ABCABCABCTimeGroupTime x Group
Sun habits/sun protection behaviour
How often do you sunbathe with the intention to tan during the summer in Sweden?-0.17-0.12-0.29a -0.35b 0.06-0.30a -0.37b -0.06-0.43b <0.0010.9790.402
How often do you usually go on a ‘sun vacation‘ abroad?-
Do you usually use a sunscreen when sunbathing?0.16-0.24-0.08-0.39a 0.21-0.18-0.09-0.09-0.180.1250.7870.032
If you use sunscreens, which sun protection factor do you choose?-0.19-0.34-0.54a -0.54a -0.30-0.84b -0.23-0.20-0.43<0.0010.2810.371
When in the sun, without intention to tan, how often do you use any of the following ways to protect from the sun:
(a) sunscreens0.22-0.220.00-0.53b 0.19-0.34-0.07-0.14-0.200.0930.4570.004
(b) shirt or sweater with short sleeves-0.16-0.07-0.230.00-0.25-0.25-0.19-0.12-0.310.0090.8050.708
(c) shirt or sweater with long sleeves-0.08-0.00-0.08-0.220.06-0.17-0.16-0.16-0.320.0180.1990.654
(d) sun hat or cap-0.06-0.03-0.09-0.24-0.00-0.24-0.14-0.06-0.210.0680.0380.890
(e) trousers with long legs-0.230.09-0.14-0.35a -0.03-0.38a -0.22-0.00-0.23<0.0010.8640.677
(f) staying in the shade-0.11-0.23-0.34a -0.29c 0.04-0.25-0.18-0.20-0.38a <0.0010.1110.384
How many times have you been sunburnt during the past year?-0.090.04-0.05-0.19c -0.02-0.21-0.20c -0.07-0.27a <0.0010.9070.291
How often do you use a sunbed?-0.15c -0.01-0.17-0.130.02-0.11-0.16c -0.15a -0.31b <0.0010.5420.109
How long do you usually stay in the sun between 11am and 3pm (Jun–Aug)?-0.30c -0.10-0.40a -0.40a -0.18-0.58b -0.06-0.21-0.27<0.0010.7910.222
Propensity to increase sun protection
Giving up sunbathing-0.47a -0.17-0.65b -0.63b -0.03-0.66b -0.49a -0.24-0.76b <0.0010.5100.909
Using clothes for sun protection-0.220.04-0.17-0.260.08-0.18-0.29-0.07-0.350.0060.1990.925
Using sunscreens-0.070.03-0.05-0.320.28-0.04-0.090.04-0.050.1310.5570.658
Staying in the shade-0.34c 0.76b 0.42a -0.74b 0.93b 0.19-0.220.82b 0.60b <0.0010.6260.073
Attitudes towards sun exposure
How do you like sunbathing?-0.11-0.18-0.29a -0.10-0.00-0.100.03-0.11-0.080.0150.2790.333
Do you think that the advantages of sunbathing outweigh the disadvantages?-0.29c -0.15-0.44b -0.290.14-0.15-0.04-0.22-0.26<0.0010.8850.139
How extensive do you consider the health risks of sunbathing?-0.06-0.14-0.20-0.35a 0.19-0.160.08-0.05-0.030.0790.8950.028
How extensive do you consider the risk for you to develop skin cancer?-0.11-0.02-0.14-0.070.00-0.060.00-0.19-0.190.0340.3290.531
How important is it for you to get tanned during the summer?-0.08-0.11-0.18c 0.01-0.14-0.13-0.15-0.13-0.28a <0.0010.0770.542
SEPI score -0.45-0.37-0.82-2.20b 0.15-2.04b -1.20a -0.83-2.04b <0.0010.3120.005
  • a P<0.01. b P<0.001. c P<0.05.

  • A = change baseline to 3 years. B = change 3 to 10 years. C = change baseline to 10 years.

  • A negative value indicates change towards lowered risk behaviour, increased propensity to change behaviour, and lowered risk attitude, respectively. Šidák adjustment for multiple comparisons.