Perceptions of Health Risks and Benefits of Cannabis Use Among College Students: Prevalence and Associations With Cannabis Use.

OBJECTIVE: Health decision-making is influenced by perceived health risks and benefits. Greater understanding of these perceptions in college students, a population engaging in high rates of risky cannabis use, is needed. The primary aim of the current study was to examine both perceived risks and benefits of cannabis for short- and long-term health consequences and how these perceptions relate to cannabis use and related problems. METHOD: Using a large, diverse college sample from 10 institutions across the United States (N = 2,354), this cross-sectional study assessed health perceptions of cannabis, cannabis use, and related problems. We examined endorsement of various health perceptions by cannabis use status (never, lifetime, current) and other demographic factors. RESULTS: Participants endorsed a number of health risks (e.g., birth defects, memory problems) and benefits (e.g., pain relief, anxiety reduction) associated with cannabis use. Overall, there was stronger endorsement of health risks than benefits, although this relationship was reversed for individuals who currently use. With a few exceptions, perceptions of health risks and benefits did not differ across demographic variables, including state-level legal status of cannabis. Among individuals reporting past-month use, benefit perceptions were associated with more frequent use, and risk perceptions were associated with less frequent use. CONCLUSIONS: Detailed and nuanced understanding of perceived health risks and benefits could be used to identify common beliefs about cannabis and to develop prevention messaging and intervention targets, such as correcting normative beliefs or addressing misconceptions about the health risks and benefits of cannabis.

Longitudinal comparisons of self-affirmation approaches for sun protection.

OBJECTIVES: Self-affirmation approaches for health behaviour demonstrate consistent small to medium effects on message acceptance, health intentions and behaviour change. There are several forms of self-affirmation (e.g., values affirmations, implementation intentions), but few empirical comparisons to guide selection in empirical work. Further, there has been little emphasis on the putative mechanisms of self-affirmation driving behaviour change. The current investigation compared a control and four self-affirmation approaches: values, social, implementation intention, and perspective taking. METHODS: Participants were recruited through CloudResearch (N = 666) and reported baseline sun exposure and protection behaviour at Time 1. One week later (Time 2), returning participants (N = 535) were randomly assigned to condition, viewed a message conveying risks of sun exposure, and reported sun exposure and protection intentions for the next week. Follow-up one week later (Time 3; N = 449) assessed past week sun exposure (i.e., number of days spent outside during peak hours), sun protection behaviour (e.g., sunscreen use), future sun exposure and protection intentions and engagement with resources conveying further health information (i.e., viewing infographics, following links to websites with more information). The association of putative mechanisms with self-affirmation conditions and health outcomes was also examined. RESULTS: Unexpectedly, there were few differences between self-affirmation conditions and the control on intentions, information seeking, or behaviour at follow-up. At follow-up, perspective circle participants reported fewer days spent outside, spent longer viewing infographics, and, along with social values participants, followed more weblinks seeking information than control participants. The putative mechanisms were unrelated to health outcomes. CONCLUSIONS: The current investigation was a first step in comparing novel online self-affirmation approaches and had largely null findings. Results suggest that the perspective circle performed best at promoting information seeking and, to some extent, behaviour change. Suggestions for future directions are discussed.

Young Adult Cannabis Users' Perceptions of Cannabis Risks and Benefits by Chronic Pain Status.

Purpose: Young adults experiencing chronic pain may self-medicate with cannabis. We examined perceived risks and benefits of cannabis use among young adult users by chronic pain status, and identified relationships among perceived risks and benefits, physical and mental health, and cannabis-related problems. Methods: Young adults reporting at least weekly cannabis use (N = 176, 50.9% with chronic pain) reported perceptions of lifetime risks and benefits associated with cannabis use, physical and mental health, and cannabis-related problems. Results: Young adults without chronic pain reported better physical and mental health than those with chronic pain. Cannabis use, problems, and risk and benefit perceptions did not differ by pain status. Risk and benefit perceptions were unrelated to physical health, perceiving fewer risks and more benefits was associated with better mental health, and perceiving more risk was associated with cannabis problems. Chronic pain status moderated the relationship between perceived benefits and outcomes, such that perceiving more benefits was associated with better physical health for those without chronic pain. Further, greater perceived benefits were associated with more cannabis-related problems for those without chronic pain but fewer problems for those with chronic pain. Conclusion: This study offers insight into the perceptions of risks and benefits among young adult cannabis users and associations with physical and mental health and cannabis-related problems. The effects of perceived benefits on physical health and cannabis-related problems differs for young adults with and without pain, suggesting assessment and consideration of pain status may be valuable in intervention contexts.

Worry as a mechanism of the relationship between perceived new knowledge and discouragement to smoke elicited from graphic cigarette warnings.

Evidence supports the use of graphic warnings to educate the public about the health harms of smoking and suggests warnings eliciting negative emotional responses may be more effective. This study aimed to replicate a preliminary theory-based model whereby perceived new knowledge promotes discouragement from smoking through its impact on worry about smoking with a different sample and using a new set of cigarette graphic warnings. We explored if the pattern extended to encouragement to use e-cigarettes, and if age and user group moderated the indirect effects of these models. Exclusive smokers, dual/e-cigarette users and nonusers (N = 412) evaluated graphic cigarette warnings on perceived new knowledge and worry about health harms of smoking, discouragement to smoke, and encouragement to use e-cigarettes. Perceived new knowledge was both directly and indirectly associated with discouragement to smoke through worry about health harms of smoking, and did not vary as a function of age or user group. In contrast, perceived new knowledge was not directly or indirectly associated with encouragement to use e-cigarettes, and this pattern largely did not vary as a function of age or user group. Graphic cigarette warnings that enhance knowledge may discourage smoking both directly and indirectly through worry elicited by them, and may have less impact on encouraging e-cigarette use. These findings replicate prior work and generalize to different user groups and new warnings planned for implementation in the U.S.

A latent profile analysis using the theory of planned behavior to predict alcohol use.

OBJECTIVE: The current study sought to identify subgroups of adult drinkers who differ in their level of association between alcohol-related Theory of Planned Behavior (TPB) constructs (attitudes, perceived norms, self-efficacy, and intentions), and explore if distinct subgroup profiles relate to alcohol use two weeks later. DESIGN: Participants (N = 121) were recruited to participate in a two-week study about daily experiences with exercise and alcohol (Mage = 30.93; SDage = 9.88; 59.2% female; 71.1% Caucasian). MAIN OUTCOME MEASURES: Alcohol attitudes, subjective norms, alcohol refusal self-efficacy, and intentions were used to create class membership. Behavioral outcomes included (1) drinking frequency, (2) drinking quantity, and (3) drinking to get drunk. RESULTS: Two classes of drinkers were determined - Class 1 was categorized by moderate scores on all constructs, whereas Class 2 was categorized by moderate scores on attitudes and high scores on norms, alcohol refusal self-efficacy, and intentions. Class designation was associated with frequency, but not quantity of use. CONCLUSION: The current study suggests that a minority of individuals who score moderately across all constructs should receive intervention efforts that focus on just those included in the TPB, while the vast majority may require additional constructs to be addressed.

Theory of Planned Behavior Analysis of Social Distancing During the COVID-19 Pandemic: Focusing on the Intention-Behavior Gap.

BACKGROUND: As COVID-19 continues to spread globally, it is important to understand psychological factors that may influence compliance with social distancing. PURPOSE: The present study examined whether Theory of Planned Behavior (TPB) constructs were associated with social distancing, with a focus on exploring moderators of the intention-behavior relationship. METHODS: Using a longitudinal design, U.S. adults (N = 507) self-reported TPB constructs and social distancing behavior at baseline and 3 months later. Participants were from 48 U.S. States and the District of Columbia and were on average 50.39 years old (SD = 15.32, range = 18-80). The majority were Non-Hispanic White (71.6%), had a bachelor's degree or higher (55.3%), and resided in suburban areas (55.8%). RESULTS: While positive attitudes toward social distancing increased over time (p = .002), subjective norms weakened (p < .001) and perceived behavioral control (PBC) remained stable (p = .22). Interestingly, despite an increase in intentions from baseline to follow-up (p < .001), there was a significant decrease in social distancing behavior over time (p < .001). Consistent with the TPB, baseline attitudes (p < .001), subjective norms (p < .001), and PBC (p < .001) for social distancing were all associated with baseline intentions to social distance. In turn, baseline intentions were significantly associated with social distancing behavior at follow-up (p < .001). Younger adults (p < .001) and non-White participants (p = .002) displayed a greater intention-behavior gap relative to older and White participants. In contrast, participants with more stable intentions over time displayed a stronger intention-behavior relationship (p < .001). CONCLUSIONS: Targeting individuals' attitudes, norms, and PBC may effectively promote protective behaviors intended to mitigate the spread of COVID-19 and similar viral outbreaks. Future research should examine effective strategies for translating social distancing intentions into actions.

The impact of information about tobacco-related reproductive vs. general health risks on South Indian women's tobacco use decisions.

Smokeless tobacco use among Indian women is increasing despite prevention efforts. Evolutionary theories suggest that reproductive-aged women should be more concerned about immediate threats to reproduction than threats to survival occurring late in life. This study therefore compared an anti-tobacco intervention that emphasized near-term reproductive harms to one involving general harms occurring later in life. Scheduled Tribal women (N = 92) from Karnataka, India participated in this study. At baseline, women reported tobacco use and knowledge of harms, provided a saliva sample to assess use, and randomly viewed either a general harms presentation (GHP) or reproductive harms presentation (RHP). At followup, women reported their use, knowledge of harms and intentions to quit, and provided another saliva sample. At baseline, participants were aware of general harms but not reproductive harms. Both interventions increased knowledge of harms. Women in the RHP condition did not list more harms than women in the GHP condition, however, and the RHP was not more effective in reducing tobacco use than the GHP. In the RHP condition fetal health was particularly salient. In the GHP condition, oral health was highly salient, aligning with the local disease ecology and research on tobacco use and attractiveness.

Randomized Controlled Trial of an Alcohol-related Sexual Risk Reduction Intervention with Adolescents: The Role of Neurocognitive Activation During Risky Decision-Making.

Justice-involved youth are at a higher risk of negative outcomes from sexual activity and alcohol use relative to their non-justice involved peers. In the current study, we tested the extent to which variability in neurocognitive response (i.e., activation in the right superior parietal lobule; rSPL) during a risky decision-making task moderated the success of a sexual risk reduction intervention. In a cluster randomized trial blocked by gender, justice-involved adolescents (N = 269) first completed a risky decision-making task during a magnetic resonance imaging (MRI) session, then were assigned to an information-only control (GINFO) or sexual risk reduction intervention incorporating alcohol risk reduction content (GPI + GMET) and then re-contacted every three months for one year. Youth in the GPI + GMET intervention reported less sexual risk behavior 12 months after intervention than those in the control. Although neurocognitive activation was associated with sexual risk behavior, it did not moderate intervention outcomes. This risk-reduction intervention appears to work equally well across a range of neurocognitive responses.

Cognitive and Affective Risk Beliefs and their Association with Protective Health Behavior in Response to the Novel Health Threat of COVID-19.

The COVID-19 global pandemic is an unprecedented health threat for which behavior is critical to prevent spread and personal factors could contribute to decisions for protective action. The purpose of this study was to describe associations of COVID-19 related behaviors capturing a snapshot in time during the height of the first wave of the pandemic. We tested perceptions of likelihood and severity of infection, worry, and their associations with behavior. We further explored relationships by demographic characteristics, and tested main and interactive relationships between these characteristics and beliefs and protective behaviors. Using an online cross-sectional survey, U.S. adults (N = 795) reported their perceptions of likelihood and severity of, and worry about, contracting COVID-19 for self and others, and engagement in protective behaviors. In bivariate tests, all cognitive and affective beliefs were positively associated with hygiene behaviors, but only worry and personal and others' severity were associated with greater likelihood of social distancing. Controlling for other beliefs and demographic factors, perceived personal severity remained associated with social distancing, and worry with hygiene behaviors. How people think and feel about risk could have implications for communicating information about this novel health threat and motivating action to mitigate its spread.

Randomized Trial to Reduce Risky Sexual Behavior Among Justice-Involved Adolescents.

INTRODUCTION: Justice-involved adolescents are at high risk for sexually transmitted infections; one primary reason is co-occurring substance use. This study investigates the additive benefit of including alcohol and cannabis use content in a theory-based sexual risk reduction intervention, delivered using group-based motivational enhancement therapy. STUDY DESIGN: This study had a cluster randomized design, with randomization of single-sex clusters to 1 of 3 interventions. SETTING/PARTICIPANTS: Participants were male and female justice-involved adolescents (N=460) residing in youth detention facilities. Data were collected from 2010 to 2014; analyses were completed in 2018-2019. INTERVENTION: Adolescents were randomized to 1 of 3 motivational enhancement therapy interventions: sexual risk reduction intervention, sexual risk reduction intervention with alcohol content, or sexual risk reduction intervention with alcohol and cannabis content. MAIN OUTCOME MEASURES: The primary outcome was risky sexual behavior (aggregation of condom use and frequency of intercourse), measured every 3 months for 1 year. Secondary outcomes were theoretical mechanisms on which the intervention was based (condom use attitudes, self-efficacy, peer norms, and behavioral intentions), collected at baseline and post-test. RESULTS: Risky sexual behavior significantly decreased from baseline to 3-month follow-up (t=10.59, p<0.001) and this decrease was maintained 1 year later (t=9.04, p<0.001). Intervention was associated with improved values on all theoretical mechanisms. Although all outcomes improved over time, changes did not differ by intervention condition (p>0.29 for all). Comparisons to a historical, information-only, sexual risk reduction control arm conducted with a similar juvenile justice sample confirm the effectiveness of all 3 motivational enhancement therapy-based interventions. CONCLUSIONS: All 3 interventions were associated with decreased sexual risk up to 1 year later, suggesting that the intervention modality (motivational enhancement therapy) may resonate with this population beyond the specific substance use content. This single-session manualized intervention can be readily disseminated to juvenile justice settings. TRIAL REGISTRATION: This study is registered at www.clinicaltrials.gov NCT01170260.

Experimental Test of the Educational Impact of the Newly Proposed FDA Graphic Cigarette Warnings Among U.S. Adults.

BACKGROUND: In August 2019, the U.S. Food and Drug Administration proposed a set of 13 new graphic warnings for cigarette packaging and advertisements. PURPOSE: We evaluated these warnings relative to text-only equivalents for their ability to educate the public regarding harms of smoking and influence outcomes associated with quitting. METHODS: In an experimental within-subjects design, U.S. adult nonsmokers, smokers, and dual smoker/electronic cigarette (e-cigarette) users (N = 412) recruited from an online internet platform evaluated the newly proposed graphic warnings and corresponding text-only warnings on understandability, perceived new knowledge, worry elicited about the content of the warning, discouragement from smoking, and encouragement to use e-cigarettes. RESULTS: Graphic warnings were generally rated as providing better understanding, more new knowledge, eliciting more worry about harms of smoking, and providing more discouragement from smoking relative to text-only warnings. CONCLUSIONS: The newly proposed graphic warnings could influence important responses to warnings associated with motivation to reduce smoking.

Effects of peer versus expert exercise standards on exercise cognitions and behaviour.

Objective: This experiment examined whether people respond differently to information about where they stand relative to peer behaviour or to expert behavioural recommendations, and whether responses depend on the attainability of these standards.Design: University students (N = 345) were randomly assigned to receive information about their exercise levels relative to peer behaviour or expert recommendations, both varying in attainability, or to a no-feedback control.Main Outcome Measures: Exercise-related cognitions were assessed immediately after feedback and exercise intentions and behaviour were assessed one month later.Results: Among those who received expert recommendations, immediate perceived comparative risk as well as exercise intentions one month later were higher if the standard was more attainable. Those who received peer information reported more exercise minutes in the past week if the standard was less attainable.Conclusion: These outcomes provide evidence that attainability of the standard should be a consideration for norm- and information-based health behaviour interventions.

Reactance to anti-binge drinking messages: testing cognitive and affective mechanisms among noncollege emerging adults.

Strong health messages may result in reactance, increasing unhealthy behaviors. Reactance is purported to be derived of both cognitive and affective factors. The current study investigated the extent to which these cognitive and affective reactance components accounted for the link between message exposure on intentions and behavior. Emerging adults who never attended college (N = 244) completed an online study assessing anger and negative cognitions towards high or low threat anti-binge drinking messages. Intentions to drink and binge drink in the next week and drinking behaviors 1 week later were assessed. High threat messages elicited more anger and negative cognitions than low threat messages. High threat messages had a significant total indirect effect on intentions but had no effect on drinking behaviors. These outcomes suggest that while immediate cognitive and affect reactance has an effect on intentions, it may not influence longer-term decision making and may not outweigh benefits of strong messages.

Pain Relief as a Motivation for Cannabis Use Among Young Adult Users With and Without Chronic Pain.

This study aims to determine the rate of chronic pain in a community sample of young adult cannabis users, assess the extent to which pain relief is an important motivation for cannabis use, and explore differences in consumption patterns and problem behaviors between users with and without chronic pain. The study design was cross-sectional. Self-selected community-dwelling young adults (ages 18-29 years; n = 143) who regularly use cannabis completed an online survey. Results revealed that approximately 40% of the sample met the criteria for chronic pain, and pain relief was their primary motivation for use. There were no differences between groups with respect to frequency of use or estimated potency of their preferred strains; however, users with chronic pain reported using a wider variety of administration methods and a greater quantity of cannabis with each use. Users with chronic pain also reported more extensive histories of use, with younger age at initiation and longer duration of regular use. Despite riskier consumption patterns, there were no between-group differences in negative consequences owing to use after controlling for gender and educational status. On average, the total sample reported approximately 8 problems in the past 30 days owing to use. These findings suggest that chronic pain is commonly experienced among young adult cannabis users and pain relief is the primary motivation for users with pain. For some users, clinically significant chronic pain and pain-related interference persist despite heavy use. Cannabis users with and without chronic pain report experiencing several negative consequences owing to their use. PERSPECTIVE: This article compares motivations for cannabis use and describes differences in consumption patterns among a community sample of young adult users with and without chronic pain. This information may be useful for providers who assess and treat pain in young adults, particularly in settings that have legalized recreational use.

Effect of Including Alcohol and Cannabis Content in a Sexual Risk-Reduction Intervention on the Incidence of Sexually Transmitted Infections in Adolescents: A Cluster Randomized Clinical Trial.

Importance: Adolescents in the juvenile justice system are at high risk for sexually transmitted infections (STIs). Concurrent use of alcohol and cannabis increase this risk. Objective: To determine whether a theory-based sexual risk-reduction intervention that included alcohol- and cannabis-focused content resulted in greater reductions in STIs than an intervention that included alcohol-related content only and an intervention that did not include substance use content. Design, Setting, and Participants: Cluster randomized clinical trial with 3 conditions. Between July 1, 2010, and December 10, 2014, adolescents living at a juvenile detention facility in the southwestern United States were tested and treated for STI before randomization and again 12 months after the intervention. Data analyses were conducted in July and August 2017. Eligibility criteria included (1) being aged 14 to 18 years, (2) able to speak English, (3) having a remaining detention term of less than 1 month, and (4) signing a release granting access to STI results if tested at intake. Six hundred ninety-three adolescents were assessed for eligibility. Of these, 460 completed baseline assessments and were randomized to 1 of 3 intervention conditions. Data analysis was by intent-to-treat. Interventions: There were 3 intervention conditions: sexual risk reduction intervention (SRRI); SRRI plus alcohol content (SRRI + ETOH); and SRRI + ETOH plus cannabis content (SRRI + ETOH + THC). Interventions were conducted in same-sex groups by trained clinicians and included video presentations with discussion, group activities, and active feedback by participants, consistent with the principles of motivational enhancement therapy. Main Outcomes and Measures: Although not the outcome on which the study was originally powered, the main outcome variable presented herein is STI incidence (Chlamydia trachomatis and/or Neisseria gonorrhoeae) 12 months after the intervention. Results: Of the 460 participants randomized, mean (SD) age was 15.8 (1.1) years, 347 participants (75.4%) were male, and 57.0% were of Hispanic ethnicity. Among the participants, 143 were randomized to SSRI, 155 to SRRI + ETOH, and 162 to SRRI + ETOH + THC. Attrition at 12-month follow-up was 99 (21.5%) for the STI outcome variable. Participants in the SRRI + ETOH + THC intervention had lower incidence of STI at follow-up (3.9%) than those in either the SRRI (12.4%; odds ratio, 0.29; 95% CI, 0.10-0.84) or the SRRI + ETOH (10.2%; odds ratio, 0.36; 95% CI, 0.12-1.05) interventions. Conclusions and Relevance: An intervention delivered in a motivational enhancement therapy format that includes theory-based sexual risk reduction combined with alcohol- and cannabis-focused elements is effective at reducing STI incidence among justice-involved adolescents. This 1-session manualized intervention can be delivered in the context of short-term detention and is easily disseminated to juvenile justice agencies. Trial Registration: clinicaltrials.gov Identifier: NCT01170260.

Neural mechanisms of risky decision making in adolescents reporting frequent alcohol and/or marijuana use.

Because adolescence is a period of heightened exploration of new behaviors, there is a natural increase in risk taking including initial use of alcohol and marijuana. In order to better understand potential differences in neurocognitive functioning among adolescents who use drugs, the current study aimed to identify the neural substrates of risky decision making that differ among adolescents who are primary users of alcohol or marijuana, primary users of both alcohol and marijuana, and controls who report primary use of neither drug. Participants completed the Balloon Analogue Risk Task (BART) while undergoing functional magnetic resonance imaging. Comparison of brain activation during risky decisions versus non-risky decisions across all subjects revealed greater response to risky decisions in dorsal anterior cinguate cortex (dACC), anterior insula, ventral striatum, and lateral prefrontal cortex. Group comparisons across non-using controls, primary marijuana, primary alcohol, and alcohol and marijuana users revealed several notable differences in the recruitment of brain regions. Adolescents who use both alcohol and marijauna show decreased response during risky decision making compared to controls in insula, striatum, and thalamus, and reduced differentiation of increasing risk in dACC, insula, striatum, and superior parietal lobe compared to controls. These results provide evidence of differential engagement of risky decision making circuits among adolescents with varying levels of alcohol and marijuana use, and may provide useful targets for longitudinal studies that explicitly address causality of these differences.

A cross-sectional investigation of positive and negative smoker stereotypes and evaluations of cigarette warnings.

OBJECTIVE: Although graphic cigarette warnings have important benefits that may aid in motivating smoking quit attempts and discouraging smoking initiation, 1 possible negative consequence might be psychological reactance to graphic warnings. Reactance to warnings might be shaped by stereotypical views of smokers. This research examined the associations of positive and negative smoker stereotypes with perceptions of the educational value of warnings as well as affective and motivational responses to them. METHOD: Using a cross-sectional design, young adult smokers and nonsmokers (N = 396) completed an online questionnaire assessing positive and negative smoker stereotypes and then evaluated a series of graphic-plus-text and text-only cigarette warnings on perceived new knowledge gained from the warning, understandability of the warning, worry about the consequences of smoking elicited by the warning, and discouragement from smoking elicited by the warning. RESULTS: Negative smoker stereotypes were associated with all warning perceptions-more negative stereotypes were associated with higher levels of perceived new knowledge, perceived understandability, worry, and discouragement from smoking. Positive smoker stereotypes were only associated with more perceived new knowledge. Neither smoking status nor warning type moderated the relationships between smoking stereotypes and warning evaluations. CONCLUSIONS: Focusing on enhancing negative smoker portrayals, rather than reducing positive portrayals, may be more effective for antismoking campaigns. (PsycINFO Database Record

Comparisons of health-related and appearance-related smoking risk perceptions and worry on motivation to quit.

This research examined main and interactive associations of perceived risk and worry of health and appearance smoking consequences on motivation to quit and the relative importance of each of these. Hierarchical regressions controlling for other measures found that perceived conditional risk and worry of health consequences were associated with motivation to quit; only conditional risk of appearance consequences was associated with motivation to quit. Relative weights analysis indicated that perceived conditional risk of appearance consequences and worry about health consequences were the most important variables in the model. Consideration of appearance consequences may aid in motivating smokers to try quitting.

Do Young Adults Perceive That Cigarette Graphic Warnings Provide New Knowledge About the Harms of Smoking?

BACKGROUND: Although much research on graphic cigarette warnings has focused on motivational responses, little focus has been given to how much individuals learn from these labels. PURPOSE: This study aims to investigate whether graphic warnings provide greater perceived new knowledge of smoking consequences compared to text-only warnings, and to test a mediational model whereby perceived new knowledge promotes discouragement from smoking through its impact on worry. METHODS: In two studies, young adult smokers and nonsmokers (ages 18-25) evaluated graphic + text and corresponding text-only labels on perceived knowledge, worry about the harms addressed by the warning, and discouragement from smoking. RESULTS: Compared to text-only labels, graphic + text labels were rated as providing better understanding, more new knowledge, and being more worrisome and discouraging. Perceived new knowledge predicted greater discouragement from smoking directly and through worry. CONCLUSIONS: Graphic warnings may be more efficacious than text-based warnings in increasing knowledge and worry about harms, and discouragement from smoking.

Colorado stride (COSTRIDE): testing genetic and physiological moderators of response to an intervention to increase physical activity.

BACKGROUND: The purpose of this research was to replicate a successful intervention to increase physical activity in a different region of the country, and explore genetic and physiological moderators of intervention efficacy drawn from a transdisciplinary theoretical framework. METHOD: A randomized controlled trial comparing a print-based physical activity intervention (COSTRIDE) to a print-based health and wellness contact control (HW) intervention was conducted. Sedentary participants (n = 219) completed assessments at baseline and follow-up assessments at 3, 6, 9, and 12 months following the initiation of the intervention. RESULTS: Participants in both conditions significantly increased exercise behavior in the first six months, and then leveled off or decreased physical activity in the second six months of the study. Those in the COSTRIDE intervention increased significantly more than those in the HW intervention, and were better able to maintain their exercise behavior. Genetic factors (BDNF, rs6265; FTO, rs8044769), but not selected physiological (body temperature, blood lactate, systolic blood pressure, plasma norepinephrine, and heart rate) or subjective (perceived pain, affect) responses to physical activity, moderated response to the intervention. CONCLUSIONS: There are underlying genetic factors that influence response to behavioral intervention, and a better understanding of these factors has the potential to influence the development, targeting and tailoring of behavioral interventions to increase physical activity. TRIAL REGISTRATION: Clinicaltrials.gov registration: NCT01091857.