Furthering Scientific Inquiry for Weight Loss Maintenance: Assessing the Psychological Processes Impacted by a Low intensity Technology-Assisted Intervention (NULevel Trial).

BACKGROUND: NULevel was a randomized control trial to evaluate a technology-assisted weight loss maintenance (WLM) program in the UK. The program included: (a) a face-to-face goal-setting session; (b) an internet platform, a pedometer, and wirelessly connected scales to monitor and report diet, physical activity, and weight, and; (c) regular automated feedback delivered by mobile phone, tailored to participants' progress. Components were designed to target psychological processes linked to weight-related behavior. Though intervention participants showed increased physical activity, there was no difference in WLM between the intervention and control groups after 12 months (Sniehotta FF, Evans EH, Sainsbury K, et al. Behavioural intervention for weight loss maintenance versus standard weight advice in adults with obesity: A randomized controlled trial in the UK (NULevel Trial). PLoS Med. 2019; 16(5):e1002793. doi:10.1371/journal.pmed.1002793). It is unclear whether the program failed to alter targeted psychological processes, or whether changes in these processes failed to influence WLM. PURPOSE: We evaluate whether the program influenced 16 prespecified psychological processes (e.g., self-efficacy and automaticity toward diet and physical activity), and whether these processes (at 6 months) were associated with successful WLM (at 12 months). METHODS: 288 adults who had previously lost weight were randomized to the intervention or control groups. The control group received wireless scales and standard advice via newsletters. Assessments occurred in person at 0, 6, and 12 months. RESULTS: The intervention significantly altered 10 of the 16 psychological processes, compared with the control group. However, few processes were associated with WLM, leading to no significant indirect effects of the intervention via the processes on WLM. CONCLUSIONS: Changes in targeted processes were insufficient to support WLM. Future efforts may more closely examine the sequence of effects between processes, behavior, and WLM.

Many tools exist to help people lose weight, but it is common for people to regain that weight over time. Thus, understanding how to support the maintenance of weight loss remains a priority. The NULevel program was a 12-month weight loss maintenance (WLM) intervention for individuals who had recently lost weight. It promoted psychological factors, shown to be tied to weight-related behaviors, using face-to-face and technology-based (e.g., mobile phone feedback) elements. For example, the program encouraged making plans to improve lifestyles (e.g., exercise, better diet) and promoted people's confidence in these behaviors. However, the program was not more successful than a control condition in maintaining weight loss. We sought to understand why this occurred. We found that the program was indeed successful in influencing most of the psychological factors it targeted. Instead, it was the psychological factors that failed to predict WLM. Were the psychological factors insufficient to impact behavior? Or did the promoted behaviors fail to aid WLM? Future research should focus on answering such questions. Doing so would inform whether interventions should target different psychological factors to change behaviors, or choose different sets of behaviors to support WLM.

Applying Regulatory Focus Theory to Encourage Weight Loss in a Self-directed Intervention.

BACKGROUND: Regulatory focus theory proposes two self-regulatory systems: promotion focus-related to fulfilling aspirations and maximizing positive outcomes-and prevention focus-related to fulfilling responsibilities and avoiding negative outcomes. Building on research demonstrating associations between regulatory focus and weight outcomes, a proof-of-concept weight control intervention framed intervention procedures in terms of promotion or prevention focus and descriptively examined whether the impact of the intervention conditions depended on dispositional regulatory focus. METHODS: After random assignment to control (received pamphlet on diet and physical activity), promotion, or prevention conditions (1.5-hour baseline sessions; detailed manuals; 1-hour sessions at 3 months), community participants from a metropolitan area in the United States (N = 57; age M = 40; BMI M = 30.9) completed the Regulatory Focus Questionnaire and were weighed at baseline, 3 months, and 6 months. Longitudinal analysis was conducted with SAS Proc Mixed using restricted maximum likelihood estimation. RESULTS: Estimated weight change was -2.99 kg, 95% CI [-4.65, -1.32], in the promotion condition, -1.70 kg, 95% CI [-3.29, -0.12], in the prevention condition, and -0.18 kg, 95% CI [-1.42, 1.05], in the control condition. Exploratory analyses revealed that for relatively more promotion-focused participants, estimated weight change was -1.43 kg, 95% CI [-3.38, 0.51], in the promotion condition, +0.48 kg, 95% CI [-1.01, 1.97], in the prevention condition, and -1.09 kg, 95% CI [-2.32, 0.14], in the control condition. For relatively more prevention-focused participants, estimated weight change was -5.19 kg, 95% CI [-7.14, -3.25], in the promotion condition, -3.35 kg, 95% CI [-4.83, -1.86], in the prevention condition, and +0.42 kg, 95% CI [-0.81, 1.65], in the control condition. CONCLUSIONS: Results suggest that self-directed, promotion-focused interventions may be effective and that tailoring to self-regulatory dispositions may not be of additional benefit in initiating weight loss.

A new measure of regulatory focus: Preventing measurement error by promoting best validation practices.

OBJECTIVE AND BACKGROUND: The goals of this project were to improve our understanding of chronic regulatory focus constructs and to provide researchers with a measure that adequately assesses the constructs, can distinguish individual differences effectively across the range of the constructs, and is appropriate for use in diverse populations. METHOD: Employing best practices in construct validation, we developed the International Personality Item Pool Regulatory Focus Scale (IPIP-RFS). Utilizing 14 samples (N = 4867), we established substantive (via expert ratings and regulatory focus literature), structural (via factor analysis, item response theory, and measurement invariance), and external (via convergent, discriminant, and predictive associations) validity. RESULTS: The IPIP-RFS adequately assesses the constructs of chronic promotion focus and prevention focus, can accurately assess individuals along the continua of the constructs, and is suitable for use among populations that vary in gender, race, and age. Individual differences in promotion focus reflect self-regulation and goal pursuit related to cognitive and behavioral exploration and flexibility (i.e., plasticity), whereas individual differences in prevention focus reflect self-regulation and goal pursuit related to motivational and interpersonal steadiness (i.e., stability). CONCLUSIONS: Promotion and prevention focus are important elements of personality with broad implications for functioning and outcomes in health and other important domains.

Effects of Exposure to Conflicting Health Information on Topic-Specific Information Sharing and Seeking Intentions.

Despite considerable evidence that exposure to conflicting health information can have undesirable effects on outcomes including public understanding about and trust in health recommendations, comparatively little is known about whether such exposure influences intentions to engage in two communication behaviors central to public health promotion: information sharing and information seeking. The purpose of the current study is to test whether exposure to conflicting information influences intentions to share and seek information about six health topics. We analyzed data from two waves of a longitudinal survey experiment with a nationally representative sample of U.S. adults (N = 3,920). Participants were randomly assigned to either a conflict or no-conflict message condition, in which they read news stories and social media posts about three (of six) randomly selected health topics at Time 1 and the remaining three at Time 2. The dependent variables, which were measured at Time 2, asked participants whether they intended to share or seek information about the three topics they had just viewed. Linear mixed effects models showed that exposure to conflict reduced intentions to share and seek information, regardless of health topic. These findings suggest that exposure to conflicting health information discourages two important types of health information engagement, thus adding to the growing evidence base documenting the adverse consequences of conflicting information for public health.

Which Intervention Strategies Promote the Adoption and Maintenance of Physical Activity? Evidence From Behavioral Trials With Cancer Survivors.

BACKGROUND/PURPOSE: We address four questions about interventions to promote physical activity in cancer survivors: (a) How often is both the adoption and maintenance of behavior change tested in trials? (b) How often do interventions generate adoption-plus-maintenance of behavior change? (c) Are intervention strategies specifically geared at promoting maintenance of behavior change deployed in trials? and (d) Which intervention strategies distinguish trials that promote both the adoption and maintenance of physical activity from trials that promote adoption-only or generate no behavioral changes? METHODS: Computerized literature searches identified 206 reports of randomized trials that measured physical activity in the wake of the intervention. RESULTS: Only 51 reports (24%) measured both behavioral adoption (postintervention) and behavioral maintenance (≥3 months follow-up). The 51 reports included 58 tests of interventions; 22% of tests observed both adoption and maintenance of physical activity, 26% reported adoption-only, and 52% found no change in behavior. Change techniques designed to promote behavioral maintenance were used much less frequently than adoption techniques or adoption and maintenance techniques. Interventions that aimed to improve quality of life, used supervised exercise sessions, were undertaken in community centers, and deployed fewer behavior change techniques were associated with adoption-plus-maintenance of physical activity in cancer survivors. CONCLUSIONS: The present findings offer new insights into the adoption and maintenance of physical activity and highlight the need to routinely assess these forms of behavior change in future trials. More extensive testing of intervention strategies specifically geared at maintenance of behavior change is warranted.

Cancer survivors need to not only adopt, but also maintain, physical activity to benefit their health and wellbeing. We undertook a systematic review of interventions to promote the adoption and maintenance of physical activity in cancer survivors. Out of 206 physical activity interventions for cancer survivors that we identified, only 51 (24%) measured both the adoption and maintenance of behavior change. Of these 51 intervention studies, only 22% were effective in promoting both the adoption and maintenance of physical activity. We developed a new classification of behavior change techniques used in interventions and discovered that techniques specifically designed to promote behavioral maintenance were used only rarely. We found that interventions that aimed to improve quality of life, used supervised exercise sessions, and were undertaken in community centers predicted adoption-plus-maintenance of physical activity in cancer survivors. These findings underscore the need for more trials that assess the adoption and maintenance of physical activity and for new research programs focused on evaluating the efficacy of maintenance techniques.

Activation Versus Change as a Principle Underlying Intervention Strategies to Promote Health Behaviors.

BACKGROUND AND PURPOSE: Interventions are effective in promoting health behavior change to the extent that (a) intervention strategies modify targets (i.e., mechanisms of action), and (b) modifying targets leads to changes in behavior. To complement taxonomies that characterize the variety of strategies used in behavioral interventions, we outline a new principle that specifies how strategies modify targets and thereby promote behavior change. We distinguish two dimensions of targets-value (positive vs. negative) and accessibility (activation level)-and show that intervention strategies operate either by altering the value of what people think, feel, or want (target change) or by heightening the accessibility of behavior-related thoughts, feelings, and goals (target activation). METHODS AND RESULTS: We review strategies designed to promote target activation and find that nudges, cue-reminders, goal priming, the question-behavior effect, and if-then planning are each effective in generating health behavior change, and that their effectiveness accrues from heightened accessibility of relevant targets. We also identify several other strategies that may operate, at least in part, via target activation (e.g., self-monitoring, message framing, anticipated regret inductions, and habits). CONCLUSIONS: The Activation Vs. Change Principle (AVCP) offers a theoretically grounded and parsimonious means of distinguishing among intervention strategies. By focusing on how strategies modify targets, the AVCP can aid interventionists in deciding which intervention strategies to deploy and how to combine different strategies in behavioral trials. We outline a research agenda that could serve to further enhance the design and delivery of interventions to promote target activation.

Effects of Exposure to Conflicting Information About Mammography on Cancer Information Overload, Perceived Scientists' Credibility, and Perceived Journalists' Credibility.

Conflicting recommendations about mammography screening have received ample media coverage, emphasizing scientists' debate over the value of breast cancer screening and differences in professional organizations' guidelines about the appropriate starting age and frequency of routine mammograms. Whereas past research suggests that exposure to such media coverage of conflicting recommendations can have undesirable consequences, both on topic-specific (e.g., ambivalence about mammography) and more general outcomes (e.g., backlash toward cancer prevention recommendations), experimental evidence, especially for effects on more general health cognitions, is limited. Using data from a population-based sample of U.S. women aged 35-55 years (N = 1467), the current study experimentally tested whether exposure to news stories that varied in the level of conflict about mammography (no, low, medium, and high conflict) affected three general health cognitions-cancer information overload (CIO), perceived scientists' credibility, and perceived journalists' credibility. We further tested whether these effects varied by research literacy. Results showed that exposure to conflict increased women's perceived CIO and reduced their perceptions of journalists' credibility, and that these effects tapered off at higher levels of conflict. Exposure to conflict also reduced perceptions of scientists' credibility, but only among participants with lower levels of research literacy. Directions for future research and implications for mitigating these potentially adverse effects on public health are discussed.

Psychological Correlates of Perceived Physical Activity Engagement During the COVID-19 Pandemic Among Previously Active Individuals.

The COVID-19 pandemic altered daily life in the United States and disrupted how people engage in routine health behaviors, such as physical activity (PA). This study investigates factors that may have helped people sustain recommended levels of moderate to vigorous PA (MVPA) during this time. Using a cross-sectional design, we recruited from Amazon's Mechanical Turk in April/May 2020 a sample of individuals who reported that they had met recommended PA guidelines (≥ 150 weekly MVPA minutes; N = 397) prior to structural changes brought about by COVID-19. We assessed via self-report whether these individuals were meeting recommended levels of MVPA during the COVID-19 pandemic, their intrinsic motivation and identified regulation for exercise, exercise self-efficacy, perceived disruption to their exercise routine, and access to resources for PA. Higher identified regulation, self-efficacy, access to PA resources, and lower perceived disruption were associated with meeting PA guidelines during COVID-19. These findings provide insight into factors that may be important for continued engagement in MVPA when one experiences major disruptions to their exercise routine.Supplemental data for this article is available online at https://doi.org/10.1080/08964289.2021.1929811 .

Understanding physical activity declines during COVID-19: The affective repercussions of disruption to exercise routines.

Recent research has examined psychological factors that forestalled declines in physical activity (PA) during the early stages of the COVID-19 pandemic. Surprisingly, there has been limited evidence of an association between intrinsic motivation (IM) and PA. We reasoned that IM may have not predicted PA because COVID-19 restrictions limited opportunities to engage in exercise in ways that produced positive affective experiences (i.e., inherent rewards). Using data from a cross-sectional survey (N = 373 participants), we tested a moderated mediation model that predicted perceived changes to affective experiences during exercise would mediate the association between disruption to one's exercise routine and self-reported declines in PA, and that effects would be moderated by IM. Evidence of moderated mediation was found, suggesting that disruptions to exercise routines were associated with fewer positive affective experiences during exercise that predicted declines in PA engagement, especially for people who typically exercised for intrinsic reasons.

Effects of Social Control on Eating and Relational Behaviors in Romantic Relationships.

BACKGROUND: Prior research has shown that social control strategies can have either positive or negative effects on individuals' health behaviors. However, no research has examined the degree to which social control attempts enacted by romantic partners are associated with individuals' relational behaviors or whether perceptions of a partner's motivation to engage in social control moderate links between the use of social control and either health or relational behaviors. PURPOSE: This study investigated (a) the degree to which two classes of social control strategies that romantic partners can use to improve their partners' eating behavior (autonomy-supportive and autonomy-limiting strategies) are associated with eating and relational behaviors, and (b) whether perceptions of the partner's motivation for using social control moderate associations between its use and an individual's eating and relational behavior. METHODS: This study had a daily diary design. One hundred and forty-seven individuals in romantic relationships completed surveys for 14 consecutive days. RESULTS: On days when individuals reported that their partner used autonomy-supportive social control strategies, individuals reported healthier eating and more constructive relational behaviors. There were no effects of autonomy-limiting strategies on eating or relational behavior. Perceptions of a partner's motives did not moderate associations between reported social control and any behavioral outcomes. Moreover, there were no effects of either reported social control strategies or partner motive perceptions across time. CONCLUSION: Romantic partners' perceived use of autonomy-supportive-but not autonomy-limiting-social control has benefits for individuals' health behaviors without incurring notable costs to their romantic relationship.

Associations Between Parents' Health and Social Control Behaviors and Their Adolescent's Self-Efficacy and Health Behaviors: Insights From the Family Life, Activity, Sun, Health, and Eating (FLASHE) survey.

BACKGROUND: Parents can influence their children to live healthier lifestyles by modeling healthy behaviors and/or trying to persuade their children to engage in healthier activities. Adolescents and their parents tend to have similar eating and exercise patterns, but less is known about the simultaneous influence of parent's health behavior and social control on adolescents' self-efficacy and health behaviors, including whether their effect is moderated by parenting style. PURPOSE: We examine the degree to which parents' social control and health behaviors are associated with their adolescent's self-efficacy and health behaviors, including whether parenting styles moderate these associations. METHOD: We analyzed data from the Family Life, Activity, Sun, Health, and Eating project. RESULTS: We found that parents' own health behaviors are positively and strongly associated with their adolescent's health behaviors across four domains: fruit/vegetable consumption, junk food consumption, physical activity, and nonacademic screen time. We found positive, moderate-to-strong associations between parents' use of social control and their adolescents' fruit/vegetable and junk food consumption, small negative associations with screen time, and no associations with physical activity. The effects of social control for junk food consumption and screen time, however, depended on parents' own behavior in those domains. Parent responsiveness moderated the relation between parents' social control and their adolescent children's self-efficacy and health behaviors. CONCLUSIONS: The health behaviors parents model and their social control efforts are associated with their adolescents' beliefs and behavior. Efforts to leverage parents as sources of influence must consider the context in which influence is enacted.

Effects of Prior Exposure to Conflicting Health Information on Responses to Subsequent Unrelated Health Messages: Results from a Population-Based Longitudinal Experiment.

BACKGROUND: Accumulating evidence suggests that exposure to conflicting health information can adversely affect public understanding of and trust in health recommendations. What is not known is whether prior exposure to such information renders people less receptive to subsequent unrelated health messages about behaviors for which the evidence is clear and consistent. PURPOSE: This study tests this "carryover" effects hypothesis, positing that prior exposure to conflict will reduce receptivity to subsequent unrelated health messages, and examines potential affective and cognitive pathways through which such effects might occur. METHODS: A three-wave, online, population-based survey experiment (N = 2,716) assessed whether participants who were randomly assigned to view a series of health news stories and social media posts featuring conflict at Times 1 and 2 were ultimately less receptive at Time 3 to ads from existing health campaigns about behaviors for which there is scientific consensus, compared to those who saw the same series of stories and posts that did not feature conflict. RESULTS: Structural equation modeling revealed evidence of carryover effects of exposure to conflict on two dimensions of message receptivity: greater resistance to the unrelated ads and lower perceptions of the health behaviors featured in the ads. Modeling indicated that carryover effects were a function of generalized backlash toward health recommendations and research elicited by prior exposure to conflicting information. CONCLUSIONS: Findings suggest that the broader public information environment, which is increasingly characterized by messages of conflict and controversy, could undermine the success of large-scale public health messaging strategies.

Americans' perceptions of health disparities over the first year of the COVID-19 pandemic: Results from three nationally-representative surveys.

COVID-19 has illuminated health inequity in the United States. The burdens of disease are much higher among Black and Indigenous people and other people of color. Disparities by income are also profound, as lower-wage workers were less able to adopt mitigating behaviors compared to higher-income counterparts. These disparities became part of public health discourse in 2020, with commentators frequently highlighting the connection between racism, socioeconomic position, and COVID-19. But what proportion of the public-and among key subgroups-recognized these social group disparities, relative to disparities associated with age and chronic illness, and did public recognition change over the first year of the pandemic? To address these questions, we analyzed data from three nationally-representative cross-sectional public opinion surveys, collected using the NORC AmeriSpeak panel in April 2020 (N = 1007), August 2020 (N = 2716), and April 2021 (N = 1020). The key outcomes were respondents' agreement with statements about disparities in COVID-19 mortality by age, chronic illness, income, and race. We found little change from 2020 to 2021 in Americans' recognition of disparities. At all three time points, most respondents acknowledged age and chronic illness disparities, while no more than half at any time point recognized income- and race-based disparities. Political party affiliation was not statistically associated with agreement with age or illness-related disparities, but was strongly associated with views about income- and race-based disparities. Efforts to promote recognition of racial and socioeconomic health disparities in the United States need to be mindful of the ways in which public understanding of health inequities is linked to partisanship.

The Dyadic Health Influence Model.

Relationship partners affect one another's health outcomes through their health behaviors, yet how this occurs is not well understood. To fill this gap, we present the Dyadic Health Influence Model (DHIM). The DHIM identifies three routes through which a person (the agent) can impact the health beliefs and behavior of their partner (the target). An agent may (a) model health behaviors and shape the shared environment, (b) enact behaviors that promote their relationship, and/or (c) employ strategies to intentionally influence the target's health behavior. A central premise of the DHIM is that agents act based on their beliefs about their partner's health and their relationship. In turn, their actions have consequences not only for targets' health behavior but also for their relationship. We review theoretical and empirical research that provides initial support for the routes and offer testable predictions at the intersection of health behavior change research and relationship science.

What Is Slowing Us Down? Six Challenges to Accelerating Advances in Health Behavior Change.

BACKGROUND: Accelerating advances in health behavior change requires releasing the brake, as well as applying the throttle. This paper discusses six challenges or "brakes" that have slowed progress. PURPOSE/METHODS/RESULTS: We engage with six issues that limit investigators' ability to delineate and test the strategy-target and target-behavior relations that underlie effective interventions according to the experimental medicine approach. We discuss the need for guidance on how to identify the relevant mechanism of action (target) in an intervention and whether a periodic table of health behavior constructs might aid investigators. Experimental and correlational analyses (prospective surveys and behavior change techniques) have been used to test the validity of targets, and we present evidence that there is little agreement among the findings from different research designs. Whereas target engagement is typically analyzed in terms of increasing scores on constructs that impel behavior change, we discuss the role of impeding targets and the benefits of adopting a broader construal of potential targets and approaches to engagement. There is presently a paucity of competitive tests regarding which strategies best engage targets and we discuss empirical criteria and conceptual developments that could enhance the evidence base. Finally, we highlight the need to take "context" or conditional intervention effects more seriously by leveraging the interplay between questions about why interventions work and questions about when and for whom they work. CONCLUSION: Candid appraisal of the challenges facing research on health behavior change can generate new opportunities for theoretical development and offer direction and cumulative impetus for empirical work.

Do Combinations of Behavior Change Techniques That Occur Frequently in Interventions Reflect Underlying Theory?

BACKGROUND: Behavioral interventions typically include multiple behavior change techniques (BCTs). The theory informing the selection of BCTs for an intervention may be stated explicitly or remain unreported, thus impeding the identification of links between theory and behavior change outcomes. PURPOSE: This study aimed to identify groups of BCTs commonly occurring together in behavior change interventions and examine whether behavior change theories underlying these groups could be identified. METHODS: The study involved three phases: (a) a factor analysis to identify groups of co-occurring BCTs from 277 behavior change intervention reports; (b) examining expert consensus (n = 25) about links between BCT groups and behavioral theories; (c) a comparison of the expert-linked theories with theories explicitly mentioned by authors of the 277 intervention reports. RESULTS: Five groups of co-occurring BCTs (range: 3-13 BCTs per group) were identified through factor analysis. Experts agreed on five links (≥80% of experts), comprising three BCT groups and five behavior change theories. Four of the five BCT group-theory links agreed by experts were also stated by study authors in intervention reports using similar groups of BCTs. CONCLUSIONS: It is possible to identify groups of BCTs frequently used together in interventions. Experts made shared inferences about behavior change theory underlying these BCT groups, suggesting that it may be possible to propose a theoretical basis for interventions where authors do not explicitly put forward a theory. These results advance our understanding of theory use in multicomponent interventions and build the evidence base for further understanding theory-based intervention development and evaluation.

Behavioural intervention for weight loss maintenance versus standard weight advice in adults with obesity: A randomised controlled trial in the UK (NULevel Trial).

BACKGROUND: Scalable weight loss maintenance (WLM) interventions for adults with obesity are lacking but vital for the health and economic benefits of weight loss to be fully realised. We examined the effectiveness and cost-effectiveness of a low-intensity technology-mediated behavioural intervention to support WLM in adults with obesity after clinically significant weight loss (≥5%) compared to standard lifestyle advice. METHODS AND FINDINGS: The NULevel trial was an open-label randomised controlled superiority trial in 288 adults recruited April 2014 to May 2015 with weight loss of ≥5% within the previous 12 months, from a pre-weight loss BMI of ≥30 kg/m2. Participants were self-selected, and the majority self-certified previous weight loss. We used a web-based randomisation system to assign participants to either standard lifestyle advice via newsletter (control arm) or a technology-mediated low-intensity behavioural WLM programme (intervention arm). The intervention comprised a single face-to-face goal-setting meeting, self-monitoring, and remote feedback on weight, diet, and physical activity via links embedded in short message service (SMS). All participants were provided with wirelessly connected weighing scales, but only participants in the intervention arm were instructed to weigh themselves daily and told that they would receive feedback on their weight. After 12 months, we measured the primary outcome, weight (kilograms), as well as frequency of self-weighing, objective physical activity (via accelerometry), psychological variables, and cost-effectiveness. The study was powered to detect a between-group weight difference of ±2.5 kg at follow-up. Overall, 264 participants (92%) completed the trial. Mean weight gain from baseline to 12 months was 1.8 kg (95% CI 0.5-3.1) in the intervention group (n = 131) and 1.8 kg (95% CI 0.6-3.0) in the control group (n = 133). There was no evidence of an effect on weight at 12 months (difference in adjusted mean weight change from baseline: -0.07 [95% CI 1.7 to -1.9], p = 0.9). Intervention participants weighed themselves more frequently than control participants and were more physically active. Intervention participants reported greater satisfaction with weight outcomes, more planning for dietary and physical activity goals and for managing lapses, and greater confidence for healthy eating, weight loss, and WLM. Potential limitations, such as the use of connected weighing study in both trial arms, the absence of a measurement of energy intake, and the recruitment from one region of the United Kingdom, are discussed. CONCLUSIONS: There was no difference in the WLM of participants who received the NULevel intervention compared to participants who received standard lifestyle advice via newsletter. The intervention affected some, but not all, process-related secondary outcomes of the trial. TRIAL REGISTRATION: This trial is registered with the ISRCTN registry (ISRCTN 14657176; registration date 20 March 2014).

Effects of Media Exposure to Conflicting Information About Mammography: Results From a Population-based Survey Experiment.

BACKGROUND: Although there is growing theoretical and empirical support for the proposition that media exposure to conflicting health information negatively influences public understanding and behavior, few studies have causally linked exposure to conflict with undesirable outcomes. Such outcomes might be particularly likely in the context of mammography, given widespread media attention to conflicting recommendations about the age at and frequency with which average-risk women should be screened for breast cancer. PURPOSE: The current study tests whether exposure to conflicting information about mammography negatively influences women's affective and cognitive responses and examines whether effects vary by socioeconomic position. METHODS: We conducted an online survey experiment in 2016 with a population-based sample of U.S. women aged 35-55 (N = 1,474). Participants were randomly assigned to one of four conditions that differed in the level of conflict about mammography presented in a news story (no, low, medium, or high conflict), stratifying by poverty level. RESULTS: Greater exposure to conflict increased women's negative emotional responses to the story they read, their confusion about and backlash toward cancer prevention recommendations and research, and their ambivalence about mammography and other types of cancer screening, though ambivalence leveled off at high levels of exposure. There was little evidence that effects varied across socioeconomic position. CONCLUSIONS: Findings add to the growing evidence base documenting undesirable outcomes of exposure to conflicting health information. Future research should examine whether the negative affective and cognitive responses observed translate into behavior, which could have implications for both health campaigns and patient-provider communication.

Links Between Behavior Change Techniques and Mechanisms of Action: An Expert Consensus Study.

BACKGROUND: Understanding the mechanisms through which behavior change techniques (BCTs) can modify behavior is important for the development and evaluation of effective behavioral interventions. To advance the field, we require a shared knowledge of the mechanisms of action (MoAs) through which BCTs may operate when influencing behavior. PURPOSE: To elicit expert consensus on links between BCTs and MoAs. METHODS: In a modified Nominal Group Technique study, 105 international behavior change experts rated, discussed, and rerated links between 61 frequently used BCTs and 26 MoAs. The criterion for consensus was that at least 80 per cent of experts reached agreement about a link. Heat maps were used to present the data relating to all possible links. RESULTS: Of 1,586 possible links (61 BCTs × 26 MoAs), 51 of 61 (83.6 per cent) BCTs had a definite link to one or more MoAs (mean [SD] = 1.44 [0.96], range = 1-4), and 20 of 26 (76.9 per cent) MoAs had a definite link to one or more BCTs (mean [SD] = 3.27 [2.91], range = 9). Ninety (5.7 per cent) were identified as "definite" links, 464 (29.2 per cent) as "definitely not" links, and 1,032 (65.1 per cent) as "possible" or "unsure" links. No "definite" links were identified for 10 BCTs (e.g., "Action Planning" and "Behavioural Substitution") and for six MoAs (e.g., "Needs" and "Optimism"). CONCLUSIONS: The matrix of links between BCTs and MoAs provides a basis for those developing and synthesizing behavioral interventions. These links also provide a framework for specifying empirical tests in future studies.

Behavior Change Techniques and Their Mechanisms of Action: A Synthesis of Links Described in Published Intervention Literature.

BACKGROUND: Despite advances in behavioral science, there is no widely shared understanding of the "mechanisms of action" (MoAs) through which individual behavior change techniques (BCTs) have their effects. Cumulative progress in the development, evaluation, and synthesis of behavioral interventions could be improved by identifying the MoAs through which BCTs are believed to bring about change. PURPOSE: This study aimed to identify the links between BCTs and MoAs described by authors of a corpus of published literature. METHODS: Hypothesized links between BCTs and MoAs were extracted by two coders from 277 behavior change intervention articles. Binomial tests were conducted to provide an indication of the relative frequency of each link. RESULTS: Of 77 BCTs coded, 70 were linked to at least one MoA. Of 26 MoAs, all but one were linked to at least one BCT. We identified 2,636 BCT-MoA links in total (mean number of links per article = 9.56, SD = 13.80). The most frequently linked MoAs were "Beliefs about Capabilities" and "Intention." Binomial test results identified up to five MoAs linked to each of the BCTs (M = 1.71, range: 1-5) and up to eight BCTs for each of the MoAs (M = 3.63, range: 1-8). CONCLUSIONS: The BCT-MoA links described by intervention authors and identified in this extensive review present intervention developers and reviewers with a first level of systematically collated evidence. These findings provide a resource for the development of theory-based interventions, and for theoretical understanding of intervention evaluations. The extent to which these links are empirically supported requires systematic investigation.