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.

Long-term effectiveness of COVID-19 vaccines against infections, hospitalisations, and mortality in adults: findings from a rapid living systematic evidence synthesis and meta-analysis up to December, 2022.

BACKGROUND: Synthesising evidence on the long-term vaccine effectiveness of COVID-19 vaccines (BNT162b2 [Pfizer-BioNTech], mRNA-1273 [Moderna], ChAdOx1 nCoV-19 [AZD1222; Oxford-AstraZeneca], and Ad26.COV2.S [Janssen]) against infections, hospitalisations, and mortality is crucial to making evidence-based pandemic policy decisions. METHODS: In this rapid living systematic evidence synthesis and meta-analysis, we searched EMBASE and the US National Institutes of Health's iSearch COVID-19 Portfolio, supplemented by manual searches of COVID-19-specific sources, until Dec 1, 2022, for studies that reported vaccine effectiveness immediately and at least 112 days after a primary vaccine series or at least 84 days after a booster dose. Single reviewers assessed titles, abstracts, and full-text articles, and extracted data, with a second reviewer verifying included studies. The primary outcomes were vaccine effectiveness against SARS-CoV-2 infections, hospitalisations, and mortality, which were assessed using three-level meta-analytic models. This study is registered with the National Collaborating Centre for Methods and Tools, review 473. FINDINGS: We screened 16 696 records at the title and abstract level, appraised 832 (5·0%) full texts, and initially included 73 (0·4%) studies. Of these, we excluded five (7%) studies because of critical risk of bias, leaving 68 (93%) studies that were extracted for analysis. For infections caused by any SARS-CoV-2 strain, vaccine effectiveness for the primary series reduced from 83% (95% CI 80-86) at baseline (14-42 days) to 62% (53-69) by 112-139 days. Vaccine effectiveness at baseline was 92% (88-94) for hospitalisations and 91% (85-95) for mortality, and reduced to 79% (65-87) at 224-251 days for hospitalisations and 86% (73-93) at 168-195 days for mortality. Estimated vaccine effectiveness was lower for the omicron variant for infections, hospitalisations, and mortality at baseline compared with that of other variants, but subsequent reductions occurred at a similar rate across variants. For booster doses, which covered mostly omicron studies, vaccine effectiveness at baseline was 70% (56-80) against infections and 89% (82-93) against hospitalisations, and reduced to 43% (14-62) against infections and 71% (51-83) against hospitalisations at 112 days or later. Not enough studies were available to report on booster vaccine effectiveness against mortality. INTERPRETATION: Our analyses indicate that vaccine effectiveness generally decreases over time against SARS-CoV-2 infections, hospitalisations, and mortality. The baseline vaccine effectiveness levels for the omicron variant were notably lower than for other variants. Therefore, other preventive measures (eg, face-mask wearing and physical distancing) might be necessary to manage the pandemic in the long term. FUNDING: Canadian Institutes of Health Research and the Public Health Agency of Canada.

How well do covariates perform when adjusting for sampling bias in online COVID-19 research? Insights from multiverse analyses.

COVID-19 research has relied heavily on convenience-based samples, which-though often necessary-are susceptible to important sampling biases. We begin with a theoretical overview and introduction to the dynamics that underlie sampling bias. We then empirically examine sampling bias in online COVID-19 surveys and evaluate the degree to which common statistical adjustments for demographic covariates successfully attenuate such bias. This registered study analysed responses to identical questions from three convenience and three largely representative samples (total N = 13,731) collected online in Canada within the International COVID-19 Awareness and Responses Evaluation Study ( www.icarestudy.com ). We compared samples on 11 behavioural and psychological outcomes (e.g., adherence to COVID-19 prevention measures, vaccine intentions) across three time points and employed multiverse-style analyses to examine how 512 combinations of demographic covariates (e.g., sex, age, education, income, ethnicity) impacted sampling discrepancies on these outcomes. Significant discrepancies emerged between samples on 73% of outcomes. Participants in the convenience samples held more positive thoughts towards and engaged in more COVID-19 prevention behaviours. Covariates attenuated sampling differences in only 55% of cases and increased differences in 45%. No covariate performed reliably well. Our results suggest that online convenience samples may display more positive dispositions towards COVID-19 prevention behaviours being studied than would samples drawn using more representative means. Adjusting results for demographic covariates frequently increased rather than decreased bias, suggesting that researchers should be cautious when interpreting adjusted findings. Using multiverse-style analyses as extended sensitivity analyses is recommended.

Understanding national trends in COVID-19 vaccine hesitancy in Canada: results from five sequential cross-sectional representative surveys spanning April 2020-March 2021.

OBJECTIVE: To examine rates of vaccine hesitancy and their correlates among Canadian adults between April 2020 and March 2021. DESIGN: Five sequential cross-sectional age, sex and province-weighted population-based samples who completed online surveys. SETTING: Canada. PARTICIPANTS: A total of 15 019 Canadians aged 18 years and over were recruited through a recognised polling firm (Leger Opinion). Respondents were 51.5% female with a mean age of 48.1 (SD 17.2) years (range 18-95 years) and predominantly white (80.8%). PRIMARY AND SECONDARY OUTCOME MEASURES: Rates of vaccine hesitancy over the five surveys (time points) and their sociodemographic, clinical and psychological correlates. RESULTS: A total of 42.2% of respondents reported some degree of vaccine hesitancy, which was lowest during surveys 1 (April 2020) and 5 (March 2021) and highest during survey 3 (November 2020). Fully adjusted multivariate logistic regression analyses revealed that women, those aged 50 and younger, non-white, those with high school education or less, and those with annual household incomes below the poverty line in Canada were significantly more likely to report vaccine hesitancy, as were essential and healthcare workers, parents of children under the age of 18 and those who do not get regular influenza vaccines. Endorsing prevention behaviours as important for reducing virus transmission and high COVID-19 health concerns were associated with 77% and 54% reduction in vaccine hesitancy, respectively. Having high personal financial concerns was associated with 1.33 times increased odds of vaccine hesitancy. CONCLUSIONS: Results highlight the importance of targeting vaccine efforts to specific groups by emphasising the outsized health benefits compared with risks of vaccination. Future research should monitor changes in vaccine intentions and behaviour to better understand underlying factors.

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.

Global Trends and Correlates of COVID-19 Vaccination Hesitancy: Findings from the iCARE Study.

The success of large-scale COVID-19 vaccination campaigns is contingent upon people being willing to receive the vaccine. Our study explored COVID-19 vaccine hesitancy and its correlates in eight different countries around the globe. We analyzed convenience sample data collected between March 2020 and January 2021 as part of the iCARE cross-sectional study. Univariate and multivariate statistical analyses were conducted to explore the correlates of vaccine hesitancy. We included 32,028 participants from eight countries, and observed that 27% of the participants exhibited vaccine hesitancy, with increases over time. France reported the highest level of hesitancy (47.3%) and Brazil reported the lowest (9.6%). Women, younger individuals (≤29 years), people living in rural areas, and those with a lower perceived income were more likely to be hesitant. People who previously received an influenza vaccine were 70% less likely to report COVID-19 vaccine hesitancy. We observed that people reporting greater COVID-19 health concerns were less likely to be hesitant, whereas people with higher personal financial concerns were more likely to be hesitant. Our findings indicate that there is substantial vaccine hesitancy in several countries, with cross-national differences in the magnitude and direction of the trend. Vaccination communication initiatives should target hesitant individuals (women, younger adults, people with lower incomes and those living in rural areas), and should highlight the immediate health, social and economic benefits of vaccination across these settings. Country-level analyses are warranted to understand the complex psychological, socio-environmental, and cultural factors associated with vaccine hesitancy.

International assessment of the link between COVID-19 related attitudes, concerns and behaviours in relation to public health policies: optimising policy strategies to improve health, economic and quality of life outcomes (the iCARE Study).

INTRODUCTION: In the context of a highly contagious virus with only recently approved vaccines and no cure, the key to slowing the spread of the COVID-19 disease and successfully transitioning through the phases of the pandemic, including vaccine uptake, is public adherence to rapidly evolving behaviour-based public health policies. The overall objective of the iCARE Study is to assess public awareness, attitudes, concerns and behavioural responses to COVID-19 public health policies, and their impacts, on people around the world and to link behavioural survey data with policy, mobility and case data to provide behavioural science, data-driven recommendations to governments on how to optimise current policy strategies to reduce the impact of the COVID-19 pandemic. METHODS AND ANALYSES: The iCARE study (www.icarestudy.com) uses a multiple cross-sectional survey design to capture self-reported information on a variety of COVID-19 related variables from individuals around the globe. Survey data are captured using two data capture methods: convenience and representative sampling. These data are then linked to open access data for policies, cases and population movement. ETHICS AND DISSEMINATION: The primary ethical approval was obtained from the coordinating site, the Centre intégré universitaire de santé et de services sociaux du Nord-de-l'Île-de-Montréal (REB#: 2020-2099/03-25-2020). This study will provide high-quality, accelerated and real-time evidence to help us understand the effectiveness of evolving country-level policies and communication strategies to reduce the spread of the COVID-19. Due to the urgency of the pandemic, results will be disseminated in a variety of ways, including policy briefs, social media posts, press releases and through regular scientific methods.

Ending the Pandemic: How Behavioural Science Can Help Optimize Global COVID-19 Vaccine Uptake.

Governments, public health officials and pharmaceutical companies have all mobilized resources to address the COVID-19 pandemic. Lockdowns, social distancing, and personal protective behaviours have been helpful but have shut down economies and disrupted normal activities. Vaccinations protect populations from COVID-19 and allow a return to pre-pandemic ways of living. However, vaccine development, distribution and promotion have not been sufficient to ensure maximum vaccine uptake. Vaccination is an individual choice and requires acceptance of the need to be vaccinated in light of any risks. This paper presents a behavioural sciences framework to promote vaccine acceptance by addressing the complex and ever evolving landscape of COVID-19. Effective promotion of vaccine uptake requires understanding the context-specific barriers to acceptance. We present the AACTT framework (Action, Actor, Context, Target, Time) to identify the action needed to be taken, the person needed to act, the context for the action, as well as the target of the action within a timeframe. Once identified a model for identifying and overcoming barriers, called COM-B (Capability, Opportunity and Motivation lead to Behaviour), is presented. This analysis identifies issues associated with capability, opportunity and motivation to act. These frameworks can be used to facilitate action that is fluid and involves policy makers, organisational leaders as well as citizens and families.

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.

Development and Validation of the Human Papillomavirus Attitudes and Beliefs Scale in a National Canadian Sample.

BACKGROUND: Parents' human papillomavirus (HPV) vaccination decision-making is strongly influenced by their attitudes and beliefs toward vaccination. To date, psychometrically evaluated HPV vaccination attitudes scales have been narrow in their range of measured beliefs and often limited to attitudes surrounding female HPV vaccination. The study aimed to develop a comprehensive, validated and reliable HPV vaccination attitudes and beliefs scale among parents of boys. METHODS: Data were collected from Canadian parents of 9- to 16-year-old boys using an online questionnaire completed in 2 waves with a 7-month interval. Based on existing vaccination attitudes scales, a set of 61 attitude and belief items were developed. Exploratory and confirmatory factor analyses were conducted. Internal consistency was evaluated with Cronbach's α and stability over time with intraclass correlations. RESULTS: The HPV Attitudes and Beliefs Scale (HABS) was informed by 3117 responses at time 1 and 1427 at time 2. The HABS contains 46 items organized in 9 factors: Benefits (10 items), Threat (3 items), Influence (8 items), Harms (6 items), Risk (3 items), Affordability (3 items), Communication (5 items), Accessibility (4 items), and General Vaccination Attitudes (4 items). Model fit at time 2 were: χ/df = 3.13, standardized root mean square residual = 0.056, root mean square error approximation (confidence interval) = 0.039 (0.037-0.04), comparative fit index = 0.962 and Tucker-Lewis index = 0.957. Cronbach's αs were greater than 0.8 and intraclass correlations of factors were greater than 0.6. CONCLUSIONS: The HABS is the first psychometrically-tested scale of HPV attitude and beliefs among parents of boys available for use in English and French. Further testing among parents of girls and young adults and assessing predictive validity are warranted.

Parents' decision-making about the human papillomavirus vaccine for their daughters: I. Quantitative results.

Vaccination against the human papillomavirus (HPV) is an effective primary prevention measure for HPV-related diseases. For children and young adolescents, the uptake of the vaccine is contingent on parental consent. This study sought to identify key differences between parents who obtain (acceptors) and parents who refuse (non-acceptors) the HPV vaccine for their daughters. In the context of a free, universal, school-based HPV vaccination program in Québec, 774 parents of 9-10 year-old girls completed and returned a questionnaire by mail. The questionnaire was based on the theoretical constructs of the Health Belief Model (HBM), along with constructs from other theoretical frameworks. Of the 774 parents, 88.2% reported their daughter having received the HPV vaccine. Perceived susceptibility of daughters to HPV infection, perceived benefits of the vaccine, perceived barriers (including safety of the vaccine), and cues to action significantly distinguished between parents whose daughters had received the HPV vaccine and those whose daughters had not. Other significant factors associated with daughter vaccine uptake were parents' general vaccination attitudes, anticipated regret, adherence to other routinely recommended vaccines, social norms, and positive media influence. The results of this study identify a number of important correlates related to parents' decisions to accept or refuse the HPV vaccine uptake for their daughters. Future work may benefit from targeting such factors and incorporating other health behavior theories in the design of effective HPV vaccine uptake interventions.

A response to Fu et al.'s "Educational interventions to increase HPV vaccination acceptance".

This commentary is a response to a systematic review, recently published in Vaccine, which investigates the effectiveness of educational interventions in increasing uptake of the human papillomavirus vaccine. The systematic review by Fu et al. (2014) enhances the field's understanding of human papillomavirus vaccine interventions; however, their review contains a number of conceptual and methodological limitations. This commentary begins by addressing these limitations. We then address the importance of studying human papillomavirus vaccine interventions in diverse populations, and conclude by making recommendations for future research.