The relative role of cognitive and emotional reactions in mediating the effects of a social comparison sun protection intervention

Abstract

Objective: This experiment examined the cognitive and emotional impact of two social comparison-based sun protection interventions in a sample of Southern California college students (N = 223). One of the interventions employed comparison UV photos of peers who had either much more (downward social comparison) or much less (upward social comparison) skin damage than did participants themselves. The second intervention consisted of descriptive norms information suggesting that a large majority of the participants’ peer group regularly protect their skin from the sun.

Design: Participants were randomly assigned to one of eight conditions in a 4 (Social Comparison Information: no photo vs. no comparison photos vs. upward comparison photos vs. downward comparison photos) × 2 (Descriptive Norms Information: Received vs. not received) design.

Main Outcome Measures: Emotional reactions (e.g. worry, embarrassment, relief) and sun-related cognitive reactions (perceived susceptibility, sun protection intentions) were assessed immediately. Sun protection behaviours were assessed in a surprise telephone follow-up five weeks following the intervention.

Results: The results demonstrated that the combination of seeing photos of peers who had very little sun damage and learning that a majority of one’s peers engage in regular sun protection resulted in reliably greater subsequent sun protection than all other conditions. Further, there was relatively direct evidence that both negative emotional reactions and sun protection intentions mediated this effect.

Conclusions: These findings add to the growing literature suggesting the importance of thoroughly examining the role of emotions in health behaviour decisions. Both theory and intervention efficacy would benefit from a better understanding of the relative role of cognitions and emotions in behaviour change.

Keywords:

• skin cancer
• sun protection
• emotions
• social comparison
• UV photos
• social norms

Acknowledgements

The author thanks James A. Kulik, the editors of the special edition, and three anonymous reviewers for their comments on a previous version of this manuscript, and Tori Bishop, Nikki Cayton, Kamryn Gebbi, and Hannah Lee for their help in carrying out this project.

Notes

1. It should be noted that the interventions utilized also might be expected to produce changes in a variety of other sun-related cognitions (e.g. self-efficacy, perceived costs of sun protection). Perceived susceptibility and sun protection intentions were utilized in this experiment because both have been relatively reliably affected by the PI/UVP intervention previously (e.g. Mahler et al., 2005, 2006, 2014) and both have been affected by the comparison photos (Mahler et al., 2010) and descriptive norms interventions (Mahler et al., 2008) utilized in this experiment.

2. The baseline sun protection items were similar but not identical to those used at follow-up in that several of the follow-up items were worded to reflect behaviours since participation in the intervention session whereas the baseline items assessed sun protection behaviours for the week prior to participation.

3. Given that both the descriptive norms intervention and the PI emphasized sunscreen use, we also conducted 4 × 2 ANCOVAs specifically on sunscreen use (separately for face and body) during intentional and incidental exposure. The results were quite similar to those reported above for the overall sun protection index. Specifically, those who received the PI/UVP intervention, either with or without comparison photos, reported greater sunscreen use on the face during incidental exposure (p < .02, d = .34) and on the body during both intentional (p < .05, d = .45) and incidental exposure (p < .01, d = .37) relative to controls. However, there was no difference between the combined intervention conditions and the control condition in sunscreen use on the face during sunbathing (p > .58, d = .12). Similar to the results of the overall sun protection index, those in the upward comparison condition reported greater sunscreen use on both the face and body during both intentional and incidental exposure relative to those in the downward comparison condition. However, the difference in means was significant only during intentional exposure (p < .001, d = .91; p < .01, d = .63 for face and body, respectively, during intentional exposure and p = .24, d = .16; p > .31, d = .14 for face and body, respectively, during incidental exposure). Finally, consistent with the results of the overall sun protection index, participants in the downward comparison condition generally reported sunscreen use at follow-up that was similar to those who had received no intervention and in fact actually reported significantly less sunscreen use on the face during sunbathing relative to controls (p < .01, d = .68). Only in the case of sunscreen use on the body during incidental exposure did those in the downward comparison condition report more frequent sunscreen use than did controls (p < .05, d = .27).

4. San Diego is one of the top ranking U.S. cities for percent of sunshine (68%; https://www1.ncdc.noaa.gov/pub/data/ccd-data/pctposrank.txt). There is no a priori reason to expect that the impact of the interventions on cognitive and emotional reactions would differ as a function of how sunny a particular region tends to be. In fact there is at least one study that showed the PI/UVP intervention to have very similar effects on cognitive reactions across two regions of the U.S. (Mahler et al., 2013). However, the same study showed more regional variability in impact of the intervention on behaviours.

5. Analysis of the effects of the interventions on sun protection behaviors as a function of gender demonstrated no main effects or interactions (all ps > .09). However, these findings should be interpreted cautiously given the very small number of males in this sample (i.e. Ns ranged from 3 to 6 males per condition).