What's said in a subject line? Framing the email subject lines in health messages sent to university students.

Objective To examine whether manipulating the frame used in email subject lines affects open or click-through rate. Participants: Students (N = 38,538) at a Midwestern university received emails from their health clinic about a stress management program (September - December 2017). Method: Three subject lines (Action Instruction only, Gain Frame plus Action Instruction, Non-loss Frame plus Action Instruction) were used. Each student randomly received one subject line in the first two months and one in the next two months. Email open and click-through rates were measured. Results: Emails with the Action Instruction only subject line were more likely to be opened; there was no difference in open rate between the two framed subject lines, and no effect on click-through rates. Conclusion: This study supports the benefits of action instructions to encourage behavior change but calls for further research on the effects of frames and action instructions in email subject lines.

Variety Salience and Enjoyment of Repetitiously Consumed Foods: a Field Experiment.

BACKGROUND: The formation of healthy eating habits is supported by repeatedly eating specific foods, but repetition can also reduce enjoyment of those foods. Making the variety in one's diet salient increases enjoyment of repetitiously consumed foods in a lab setting. Therefore, in a longitudinal field experiment, we tested a brief intervention to remind participants of the variety in their diet. We hypothesized that increasing salience of dietary variety would prevent declines in enjoyment of the food and increase the likelihood that participants would be willing to eat the food again later. METHOD: Participants (n = 139) ate a granola bar each day for 2 weeks. Before eating it, participants randomly assigned to the treatment condition recalled other recently consumed foods (to increase salience of dietary variety). Control subjects recalled variety in an unrelated domain (music). Participants reported their enjoyment of the granola bar after they ate it each day, and in a lab session after the study ended, the number of granola bars they took from a selection of snacks was counted. RESULTS: Self-reported feelings of enjoyment declined steadily, and contrary to our first hypothesis, increasing salience of dietary variety did not prevent this decline. Increasing salience of dietary variety did increase the likelihood that participants would choose to take the same kind of granola bar 2 weeks later. CONCLUSION: Brief exercises that make variety in one's diet more salient may not prevent reductions in enjoyment of a repetitiously consumed food, but may still support continued consumption of the food.

Reducing sugar use in coffee while maintaining enjoyment: A randomized controlled trial.

Consuming coffee without (or with less) sugar may help people lower their daily calorie intake without restrictive dieting. We tested two theory-based interventions to help people do so. One involved gradually reducing sugar over time, and the other was based on mindfulness theory. These interventions were compared to a repeated exposure (to sugar-free coffee) group. Participants in all conditions had significant increases in consumption of sugar-free coffee that lasted 6 months. The mindfulness group had a larger increase than the others. Unexpectedly, the gradual reduction intervention led to a decrease in liking for sugar-free coffee and was the least effective.

Interpersonal effects of parents and adolescents on each other's health behaviours: a dyadic extension of the theory of planned behaviour.

OBJECTIVE: Interpersonal relationships are important predictors of health outcomes and interpersonal influences on behaviours may be key mechanisms underlying such effects. Most health behaviour theories focus on intrapersonal factors and may not adequately account for interpersonal influences. We evaluate a dyadic extension of the Theory of Planned Behaviour by examining whether parent and adolescent characteristics (attitudes, subjective norms, perceived behavioural control and intentions) are associated with not only their own but also each other's intentions/behaviours. DESIGN: Using the Actor-Partner Interdependence Model, we analyse responses from 1717 parent-adolescent dyads from the Family Life, Activity, Sun, Health, and Eating study. MAIN OUTCOME MEASURES: Adolescents/parents completed self-reports of their fruit and vegetable consumption, junk food and sugary drinks consumption, engagement in physical activity, and engagement in screen time sedentary behaviours. RESULTS: Parent/adolescent characteristics are associated with each other's health-relevant intentions/behaviours above the effects of individuals' own characteristics on their own behaviours. Parent/adolescent characteristics covary with each other's outcomes with similar strength, but parent characteristics more strongly relate to adolescent intentions, whereas adolescent characteristics more strongly relate to parent behaviours. CONCLUSIONS: Parents and adolescents may bidirectionally influence each other's health intentions/behaviours. This highlights the importance of dyadic models of health behaviour and suggests intervention targets.

Data availability, reusability, and analytic reproducibility: evaluating the impact of a mandatory open data policy at the journal Cognition.

Access to data is a critical feature of an efficient, progressive and ultimately self-correcting scientific ecosystem. But the extent to which in-principle benefits of data sharing are realized in practice is unclear. Crucially, it is largely unknown whether published findings can be reproduced by repeating reported analyses upon shared data ('analytic reproducibility'). To investigate this, we conducted an observational evaluation of a mandatory open data policy introduced at the journal Cognition. Interrupted time-series analyses indicated a substantial post-policy increase in data available statements (104/417, 25% pre-policy to 136/174, 78% post-policy), although not all data appeared reusable (23/104, 22% pre-policy to 85/136, 62%, post-policy). For 35 of the articles determined to have reusable data, we attempted to reproduce 1324 target values. Ultimately, 64 values could not be reproduced within a 10% margin of error. For 22 articles all target values were reproduced, but 11 of these required author assistance. For 13 articles at least one value could not be reproduced despite author assistance. Importantly, there were no clear indications that original conclusions were seriously impacted. Mandatory open data policies can increase the frequency and quality of data sharing. However, suboptimal data curation, unclear analysis specification and reporting errors can impede analytic reproducibility, undermining the utility of data sharing and the credibility of scientific findings.

Behavioral compensation before and after eating at the Minnesota State Fair.

People regulate their eating behavior in many ways. They may respond to overeating by compensating with healthy eating behavior or increased exercise (i.e., a sensible tradeoff), or by continuing to eat poorly (i.e., disinhibition). Conversely, people may respond to a healthy eating event by subsequently eating poorly (i.e., self-licensing) or by continuing to eat healthily (i.e., promotion spillover). We propose that people may also change their behaviors in anticipation of an unhealthy eating event, a phenomenon that we will refer to as pre-compensation. Using a survey of 430 attendees of the Minnesota State Fair over two years, we explored whether, when, and how people compensated before and after this tempting eating event. We found evidence that people use both pre-compensatory and post-compensatory strategies, with a preference for changing their eating (rather than exercise) behavior. There was no evidence that people who pre-compensated were more likely to self-license by indulging in a greater number of foods or calories at the fair than those who did not. Finally, people who pre-compensated were more likely to also post-compensate. These results suggest that changing eating or exercise behavior before exposure to a situation with many tempting foods may be a successful strategy for enjoying oneself without excessively overeating.