How do behavioral public policy experts see the role of complex systems perspectives? An expert interview study.

Amidst the global momentum of behavioral insights (BI), there has been a shift from mostly nudge-based BI applications to systemic approaches. This is particularly pressing in public health, where interacting issues regularly produce unanticipated consequences. Regardless, little is known about adopting complex systems approaches in behavioral public policy. This study aims to capture current practices of international BI experts on the definition, application, drivers, and hindering factors in adopting complex systems approaches in public policy. Semi-structured individual expert interviews (n = 12) of international BI experts with extensive experience in educating, cooperating with, and/or advising public servants were analyzed with inductive content analysis. While the working definition of BI aligned with published definitions, experts varied in their descriptions of complex systems approaches and its significance for public policy, including socioecological aspects, systematic BI use across policy stages, recognizing intertwined behavior, and lack of ready-made solutions. They emphasized the importance of systems approaches, identifying drivers (e.g. need for a broader focus) and hindrances (e.g. pressure for quick results). Embracing complex systems in behavioral public policy provides a holistic perspective, extending beyond simple nudges, sometimes presumed as universally applicable. While complexity perspectives would align with policymakers' worldview, applications require more work to tailor to local situations and to evaluate. Recognizing that, given their distinct expertise content, BI expertise can be quite different from complex systems expertise. The field would benefit from clear descriptions and specialized training for effective integration and advocacy for these approaches.

In recent years, the use of behavioral insights (BI) in public policy, including health policy, has been shifting from nudges to more comprehensive approaches. This study examines how international BI experts view the use of complex systems approaches in behavioral public policy. Through interviews with 12 experts advising public servants, we found that while BI definitions align with earlier published definitions, experts interpret and apply complex systems approaches differently. Some consider socioecological factors, advocate applying the systematic use of BI throughout the policy cycle, and for some using complex systems approaches means considering intertwined nature of behavioral phenomena and that there are no one-size-fits-all solutions. Experts stress the importance of a systems approach, identifying drivers (e.g. need for a broader focus, experience-based expertise) and hindering factors (e.g. advisory settings, pressure for quick results) in its implementation. This study presents BI's evolving role in public policy, highlighting the need for complex systems approaches to address multifaceted societal challenges.

Nationally Automated Colonoscopy Performance Feedback Increases Polyp Detection: The NED APRIQOT Randomized Controlled Trial.

BACKGROUND & AIMS: Postcolonoscopy colorectal cancer incidence and mortality rates are higher for endoscopists with low polyp detection rates. Using the UK's National Endoscopy Database (NED), which automatically captures real-time data, we assessed if providing feedback of case-mix-adjusted mean number of polyps (aMNP), as a key performance indicator, improved endoscopists' performance. Feedback was delivered via a theory-informed, evidence-based audit and feedback intervention. METHODS: This multicenter, prospective, NED Automated Performance Reports to Improve Quality Outcomes Trial randomized National Health Service endoscopy centers to intervention or control. Intervention-arm endoscopists were e-mailed tailored monthly reports automatically generated within NED, informed by qualitative interviews and behavior change theory. The primary outcome was endoscopists' aMNP during the 9-month intervention. RESULTS: From November 2020 to July 2021, 541 endoscopists across 36 centers (19 intervention; 17 control) performed 54,770 procedures during the intervention, and 15,960 procedures during the 3-month postintervention period. Comparing the intervention arm with the control arm, endoscopists during the intervention period: aMNP was nonsignificantly higher (7%; 95% CI, -1% to 14%; P = .08). The unadjusted MNP (10%; 95% CI, 1%-20%) and polyp detection rate (10%; 95% CI, 4%-16%) were significantly higher. Differences were not maintained in the postintervention period. In the intervention arm, endoscopists accessing NED Automated Performance Reports to Improve Quality Outcomes Trial webpages had a higher aMNP than those who did not (aMNP, 118 vs 102; P = .03). CONCLUSIONS: Although our automated feedback intervention did not increase aMNP significantly in the intervention period, MNP and polyp detection rate did improve significantly. Engaged endoscopists benefited most and improvements were not maintained postintervention; future work should address engagement in feedback and consider the effectiveness of continuous feedback. CLINICAL TRIALS REGISTRY:  www.isrctn.org ISRCTN11126923 .

Improving oral health and related health behaviours (substance use, smoking, diet) in people with severe and multiple disadvantage: A systematic review of effectiveness and cost-effectiveness of interventions.

BACKGROUND: People experiencing homelessness co-occurring with substance use or offending ('severe and multiple disadvantage' SMD) often have high levels of poor oral health and related health behaviours (particularly, substance use, smoking, poor diet). This systematic review aimed to assess the effectiveness and cost-effectiveness of interventions in adults experiencing SMD to improve oral health and related health behaviours. METHODS AND FINDINGS: From inception to February 2023, five bibliographic databases (MEDLINE, EMBASE, PsycINFO, CINAHL, and Scopus) and grey literature were searched. Two researchers independently screened the search results. Randomized controlled trials (RCTs), comparative studies and economic evaluations were included that reported outcomes on oral health and the related health behaviours. Risk of bias was assessed and results narratively synthesized. Meta-analyses were performed where appropriate. This review was registered with PROSPERO (reg. no: CRD42020202416). Thirty-eight studies were included (published between 1991 and 2023) with 34 studies reporting about effectiveness. Most studies reported on substance use (n = 30). Interventions with a combination of housing support with substance use and mental health support such as contingent work therapy appeared to show some reduction in substance use in SMD groups. However, meta-analyses showed no statistically significant results. Most studies had short periods of follow-up and high attrition rates. Only one study reported on oral health; none reported on diet. Three RCTs reported on smoking, of which one comprising nicotine replacement with contingency management showed improved smoking abstinence at 4 weeks compared to control. Five studies with economic evaluations provided some evidence that interventions such as Housing First and enhanced support could be cost-effective in reducing substance use. CONCLUSION: This review found that services such as housing combined with other healthcare services could be effective in improving health behaviours, particularly substance use, among SMD groups. Gaps in evidence also remain on oral health improvement, smoking, and diet. High quality studies on effectiveness with adequate power and retention are needed to address these significant health challenges in SMD populations.

The Gestational Obesity Weight Management: Implementation of National Guidelines (GLOWING) study: a pilot cluster randomised controlled trial.

BACKGROUND: Pregnancy weight management interventions can improve maternal diet, physical activity, gestational weight gain, and postnatal weight retention. UK guidelines were published in 2010 but health professionals report multiple complex barriers to practice. GLOWING used social cognitive theory to address evidence-based barriers to midwives' implementation of weight management guidelines into routine practice. This paper reports the pilot trial outcomes relating to feasibility and acceptability of intervention delivery and trial procedures. METHODS: GLOWING was a multi-centre parallel-group pilot cluster RCT comparing the delivery of a behaviour change intervention for midwives (delivered as training workshops) with usual practice. The clusters were four NHS Trusts in Northeast England, randomised to intervention or control arms. Blinding of allocation was not possible due to the nature of the intervention. We aimed to deliver the intervention to all eligible midwives in the intervention arm, in groups of 6 midwives per workshop, and to pilot questionnaire data collection for a future definitive trial. Intervention arm midwives' acceptability of GLOWING content and delivery was assessed using a mixed methods questionnaire, and pregnant women's acceptability of trial procedures by interviews. Quantitative data were analysed descriptively and qualitative data thematically. RESULTS: In intervention arm Trusts, 100% of eligible midwives (n = 67) were recruited to, and received, the intervention; however, not all workshops had the planned number of attendees (range 3-8). The consent rate amongst midwives randomised (n = 100) to complete questionnaires was 74% (n = 74) (95% CI 65%, 83%), and overall completion rate 89% (n = 66) (95% CI 82%, 96%). Follow-up response rate was 66% (n = 49) (95% CI 55%, 77%), with a marked difference between intervention (39%, n = 15) and control (94%, n = 34) groups potentially due to the volume of research activities. Overall, 64% (n = 47) (95% CI 53%, 75%) completed both baseline and follow-up questionnaires. Midwives viewed the intervention as acceptable and directly relevant to routine practice. The least popular components related to scripted role-plays. Pregnant women viewed the recruitment and trial processes to be acceptable. CONCLUSIONS: This rigorously conducted pilot study demonstrated feasibility intervention delivery and a high level of acceptability amongst participants. It has provided information required to refine the intervention and trial protocol, enhancing confidence that a definitive trial could be carried out. TRIAL REGISTRATION: ISRCTN46869894; retrospectively registered 25th May 2016, www.isrctn.com/ISRCTN46869894 .

Effectiveness of shared medical appointments delivered in primary care for improving health outcomes in patients with long-term conditions: a systematic review of randomised controlled trials.

OBJECTIVES: To examine the effectiveness of shared medical appointments (SMAs) compared with one-to-one appointments in primary care for improving health outcomes and reducing demand on healthcare services by people with one or more long-term conditions (LTCs). DESIGN: A systematic review of the published literature. DATA SOURCES: Six databases, including MEDLINE and Web of Science, were searched 2013-2023. Relevant pre-2013 trials identified by forward and backward citation searches of the included trials were included. ELIGIBILITY CRITERIA: Randomised controlled trials of SMAs delivered in a primary care setting involving adults over 18 years with one or more LTCs. Studies were excluded if the SMA did not include one-to-one patient-clinician time. All countries were eligible for inclusion. DATA EXTRACTION AND SYNTHESIS: Data were extracted and outcomes narratively synthesised, meta-analysis was undertaken where possible. RESULTS: Twenty-nine unique trials were included. SMA models varied in terms of components, mode of delivery and target population. Most trials recruited patients with a single LTC, most commonly diabetes (n=16). There was substantial heterogeneity in outcome measures. Meta-analysis showed that participants in SMA groups had lower diastolic blood pressure than those in usual care (d=-0.086, 95% CI=-0.16 to -0.02, n=10) (p=0.014). No statistically significant differences were found across other outcomes. Compared with usual care, SMAs had no significant effect on healthcare service use. For example, no difference between SMAs and usual care was found for admissions to emergency departments at follow-up (d=-0.094, 95% CI=-0.27 to 0.08, n=6, p=0.289). CONCLUSIONS: There was a little difference in the effectiveness of SMAs compared with usual care in terms of health outcomes or healthcare service use in the short-term (range 12 weeks to 24 months). To strengthen the evidence base, future studies should include a wider array of LTCs, standardised outcome measures and more details on SMA components to help inform economic evaluation. PROSPERO REGISTRATION NUMBER: CRD42020173084.

Falsification of home rapid antigen lateral flow tests during the COVID-19 pandemic.

During the COVID-19 pandemic, lateral flow tests (LFTs) were used to regulate access to work, education, social activities, and travel. However, falsification of home LFT results was a concern. Falsification of test results during an ongoing pandemic is a sensitive issue. Consequently, respondents may not answer truthfully to questions about LFT falsification behaviours (FBs) when asked directly. Indirect questioning techniques such as the Extended Crosswise model (ECWM) can provide more reliable prevalence estimates of sensitive behaviors than direct questioning. Here we report the prevalence of LFT FBs in a representative sample in England (n = 1577) using direct questioning (DQ) and the ECWM. We examine the role of demographic and psychological variables as predictors of LFT FBs. We show that the prevalence estimates of the FBs in the DQ condition were significantly lower than the ECWM estimates, e.g., reporting a negative result without conducting a test: 5.7% DQ vs 18.4% ECWM. Moral norms, subjective norms, anticipated regret, perception of risk to self, and trust in government predicted some of the FBs. Indirect questioning techniques can help provide more realistic and higher quality data about compliance with behavioural regulations to government and public health agencies.

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.

5-year follow-up of the randomised Diabetes Remission Clinical Trial (DiRECT) of continued support for weight loss maintenance in the UK: an extension study.

BACKGROUND: In DiRECT, a randomised controlled effectiveness trial, weight management intervention after 2 years resulted in mean weight loss of 7·6 kg, with 36% of participants in remission of type 2 diabetes. Of 36 in the intervention group who maintained over 10 kg weight loss at 2 years, 29 (81%) were in remission. Continued low-intensity dietary support was then offered up to 5 years from baseline to intervention participants, aiming to maintain weight loss and gain clinical benefits. This extension study was designed to provide observed outcomes at 5 years. METHODS: The DiRECT trial took place in primary care practices in the UK. Participants were individuals aged 20-65 years who had less than 6 years' duration of type 2 diabetes, a BMI greater than 27 kg/m2, and were not on insulin. The intervention consisted of withdrawal of antidiabetic and antihypertensive drugs, total diet replacement (825-853 kcal per day formula diet for 12-20 weeks), stepped food reintroduction (2-8 weeks), and then structured support for weight-loss maintenance. After sharing the 2-year results with all participants, UK National Health Service data were collected annually until year 5 from remaining intervention participants who received low-intensity dietary support, intervention withdrawals, and the original randomly allocated groups. The primary outcome was remission of type 2 diabetes; having established in the DiRECT trial that sustained weight loss was the dominant driver of remission, this was assumed for the Extension study. The trial is registered with the ISRCTN registry, number 03267836. FINDINGS: Between July 25, 2014, and Aug 5, 2016, 149 participants were randomly assigned to the intervention group and 149 were assigned to the control group in the original DiRECT study. After 2 years, all intervention participants still in the trial (101 [68%] of 149) were approached to receive low-intensity support for a further 3 years. 95 (94%) of 101 were able to continue and consented and were allocated to the DiRECT extension group. 54 participants were allocated to the non-extension group, where intervention was withdrawn. At 5 years, DiRECT extension participants (n=85) lost an average of 6·1 kg, with 11 (13%) of 85 in remission. Compared with the non-extension group, DiRECT extension participants had more visits with HbA1c <48 mmol/mol (<6·5%; 36% vs 17%, p=0·0004), without glucose-lowering medication (62% vs 30%, p<0·0001), and in remission (34% vs 12%, p<0·0001). Original control participants (n=149) had mean weight loss 4·6 kg (n=82), and 5 (5%) of 93 were in remission. Compared with control participants, original intervention participants had more visits with weight more than 5% below baseline (61% vs 29%, p<0·0001), HbA1c below 48 mmol/mol (29% vs 15%, p=0·0002), without antidiabetic medication (51% vs 16%, p<0·0001), and in remission (27% vs 4%, p<0·0001). Of those in remission at year 2, 26% remained in remission at 5 years. Serious adverse events in the original intervention group (4·8 events per 100 patient-years) were under half those in the control group (10·2 per 100 patient-years, p=0·0080). INTERPRETATION: The extended DiRECT intervention was associated with greater aggregated and absolute weight loss, and suggested improved health status over 5 years. FUNDING: Diabetes UK.

Factors influencing implementation and sustainability of interventions to improve oral health and related health behaviours in adults experiencing severe and multiple disadvantage: a mixed-methods systematic review.

OBJECTIVES: Among people experiencing severe and multiple disadvantage (SMD), poor oral health is common and linked to smoking, substance use and high sugar intake. Studies have explored interventions addressing oral health and related behaviours; however, factors related to the implementation of these interventions remain unclear. This mixed-methods systematic review aimed to synthesise evidence on the implementation and sustainability of interventions to improve oral health and related health behaviours among adults experiencing SMD. METHODS: Bibliographic databases (MEDLINE, EMBASE, PsycINFO, CINAHL, EBSCO, Scopus) and grey literature were searched from inception to February 2023. Studies meeting the inclusion criteria were screened and extracted independently by two researchers. Quality appraisal was undertaken, and results were synthesised using narrative and thematic analyses. RESULTS: Seventeen papers were included (published between 1995 and 2022). Studies were mostly of moderate quality and included views from SMD groups and service providers. From the qualitative synthesis, most findings were related to aspects such as trust, resources and motivation levels of SMD groups and service providers. None of the studies reported on diet and none included repeated offending (one of the aspects of SMD). From the quantitative synthesis, no difference was observed in programme attendance between the interventions and usual care, although there was some indication of sustained improvements in participation in the intervention group. CONCLUSION: This review provides some evidence that trust, adequate resources and motivation levels are potentially important in implementing interventions to improve oral health and substance use among SMD groups. Further research is needed from high quality studies and focusing on diet in this population. PROSPERO REGISTRATION NUMBER: CRD42020202416.

Statistical analysis plan for a cluster randomised controlled trial to compare screening, feedback and intervention for child anxiety problems to usual school practice: identifying Child Anxiety Through Schools-identification to intervention (iCATS-i2i).

BACKGROUND: The Identifying Child Anxiety Through Schools-identification to intervention (iCATS-i2i) trial is being conducted to establish whether 'screening and intervention', consisting of usual school practice plus a pathway comprising screening, feedback and a brief parent-led online intervention (OSI: Online Support and Intervention for child anxiety), bring clinical and health economic benefits compared to usual school practice and assessment only - 'usual school practice', for children aged 8-9 years in the following: (1) the 'target population', who initially screen positive for anxiety problems according to a two-item parent-report child anxiety questionnaire - iCATS-2, and (2) the 'total population', comprising all children in participating classes. This article describes the detailed statistical analysis plan for the trial. METHODS AND DESIGN: iCATS-i2i is a definitive, superiority, pragmatic, school-based cluster randomised controlled trial (with internal pilot), with two parallel groups. Schools are randomised 1:1 to receive either screening and intervention or usual school practice. This article describes the following: trial objectives and outcomes; statistical analysis principles, including detailed estimand information necessary for aligning trial objectives, conduct, analyses and interpretation when there are different analysis populations and outcome measures to be considered; and planned main analyses, sensitivity and additional analyses. TRIAL REGISTRATION: ClinicalTrials.gov ISRCTN76119074. Registered on 4 January 2022.

Associations of adherence to physical activity and dietary recommendations with weight recurrence 1-5 years after metabolic and bariatric surgery.

BACKGROUND: Little is known about longer-term adherence to recommended physical activity (PA) and dietary behaviors after metabolic and bariatric surgery (MBS) and whether adherence is associated with weight recurrence. OBJECTIVES: To explore (1) changes in and associations between adherence to PA and general dietary recommendations after MBS and (2) whether PA and dietary behaviors interact to predict weight recurrence. SETTING: University hospital; public practice. METHODS: Participants completed ActiGraph PA monitoring, dietary questionnaire, and weighing 1 and 5 years after surgery. Parametric and non-parametric tests evaluated changes in and associations between adherence to PA and dietary recommendations. Multiple linear regression explored associations of adherence and weight recurrence 5 years post-surgery. RESULTS: A total of 73 participants (66% loss to follow-up, 80.8% females) were included. From 1 to 5 years after surgery, adherence to PA recommendations did not change (23.5% versus 20.5%, P = .824), whereas adherence to dietary recommendations decreased (P = <.001). Adherence to PA recommendations is positively associated with eating fruits and vegetables and limiting intake of sugar and fat at 1 year (P < .05) and negatively associated with choosing meat with less fat at 5 years (P = .018). Adherence to PA and dietary behaviors did not independently contribute or interact to predict weight recurrence. CONCLUSIONS: Adherence to recommendations was poor. Dietary adherence decreased from 1 to 5 years post-surgery, whereas PA adherence remained stable. PA adherence was positively associated with adherence to some dietary recommendations at 1 year but not at 5 years. Neither behavioral adherences were associated with weight recurrence. Additional research is needed to understand how to improve adherence and its relationship with other health outcomes after MBS.

Interventions to improve oral health and related health behaviours of substance use, smoking, and diet in people with severe and multiple disadvantage: a systematic review of effectiveness and cost-effectiveness.

BACKGROUND: Homelessness overlapping with substance use and offending is described as severe and multiple disadvantage (SMD). People experiencing SMD have poor oral health along with high levels of related behaviours such as substance use, smoking, and poor diet. Existing evidence largely describes the prevalence of oral health problems, substance use, and smoking in SMD groups. Little is known about interventions that can address these conditions in SMD groups. We aimed to review the effectiveness and cost-effectiveness of interventions on oral health and related health behaviours in adults experiencing SMD. METHODS: For this systematic review, we searched bibliographic databases (MEDLINE, EMBASE, PsycINFO, CINAHL, EBSCO, Scopus) and grey literature for papers published from inception to February 2023. Two researchers independently reviewed the searches. Randomised controlled trials (RCTs), comparative studies and economic evaluations were included. Risk of bias was assessed. Population included adults experiencing SMD (including homelessness and substance use or repeat offending). Outcomes included oral health, and related behaviours (substance use, smoking, poor diet). Results were narratively synthesised. This review was registered with PROSPERO, CRD42020202416. FINDINGS: The review included 38 studies (published between 1991 and 2023), with 34 reporting effectiveness. These studies comprised of 23 RCTs and 11 quasi-experimental studies conducted in the USA (25 studies), Canada (seven studies), France (one study), and Spain (one study). The interventions involving multiple components, such as housing services with substance use and mental health support, effectively reduced substance use in SMD groups; these were mostly individual-level interventions. However, these studies had short follow-up periods and high attrition rates. Only one study addressed oral health outcomes, none focused on diet, and three RCTs covered smoking, with one intervention showing smoking abstinence at 4 weeks. Some limited evidence suggested cost-effectiveness of substance use interventions. INTERPRETATION: This review found that integrating services such as housing with other health-care services together could be effective in improving health behaviours, especially substance use among SMD groups. More evidence is needed specifically on oral health, smoking, and diet-related interventions. The generalisability of findings of this review is limited to high-income countries and shorter-term outcomes. FUNDING: National Institute for Health and Care Research (NIHR) Policy Research Programme.

Are motivational and self-regulation factors associated with 12 months' weight regain prevention in the NoHoW study? An analysis of European adults.

PURPOSE: Preventing weight regain can only be achieved by sustained changes in energy balance-related behaviors that are associated with weight, such as diet and physical activity. Changes in motivation and self-regulatory skills can support long-term behavioral changes in the context of weight loss maintenance. We propose that experiencing a supportive climate care is associated with enhanced satisfaction of basic psychological needs, intrinsic goals, and autonomous motivation. These factors are expected to be associate with the utilization of self-regulation skills, leading to more sustained behavior changes and ultimately preventing weight regain. This hypothesis was tested in this ancillary analysis of the NoHoW trial, where the study arms were pooled and followed for 12 months. METHODS: The NoHoW was a three-center, large-scale weight regain prevention full factorial trial. In this longitudinal study, data were collected in adults who lost > 5% weight in the past year (N = 870, complete data only, 68.7% female, 44.10 ± 11.86 years, 84.47 ± 17.03 kg) during their participation in a 12-month digital behavior change intervention. Weight and validated measures of motivational- and self-regulatory skills-related variables were collected at baseline, six- and 12 months. Change variables were used in Mplus' path analytical models informed by NoHoW's logic model. RESULTS: The bivariate correlations confirmed key mediators' potential effect on weight outcomes in the expected causal direction. The primary analysis showed that a quarter of the variance (r2 = 23.5%) of weight regain prevention was achieved via the mechanisms of action predicted in the logic model. Specifically, our results show that supportive climate care is associated with needs satisfaction and intrinsic goal content leading to better weight regain prevention via improvements in self-regulatory skills and exercise-controlled motivation. The secondary analysis showed that more mechanisms of action are significant in participants who regained or maintained their weight. CONCLUSIONS: These results contribute to a better understanding of the mechanisms of action leading to behavior change in weight regain prevention. The most successful participants used only a few intrinsic motivation-related mechanisms of action, suggesting that habits may have been learned. While developing a digital behavior change intervention, researchers and practitioners should consider creating supportive climate care to improve needs satisfaction and intrinsic goal contents. TRIAL REGISTRATION: ISRCTN, ISRCTN88405328 , registered 12/22/2016.

Maternal Obesity and Patterns in Postnatal Diet, Physical Activity and Weight among a Highly Deprived Population in the UK: The GLOWING Pilot Trial.

Preconception obesity is associated with adverse pregnancy outcomes and deprivation. The postnatal period provides an opportunity for preconception intervention. There is a lack of published postnatal behaviour and weight data to inform intervention needs. Secondary analysis of the GLOWING study explored postnatal diet, physical activity (PA) and weight among women living with obesity in deprivation. Thirty-nine women completed food frequency and PA questionnaires and provided weight measurement(s) between 3-12 months postnatal. Women's diet and PA fell short of national guidelines, especially for fruit/vegetables (median 1.6-2.0 portions/day) and oily fish (0-4 g/day). PA was predominantly light intensity. Patterns in weight change across time points indicated postnatal weight loss compared with 1st (median -0.8 to -2.3 kg) and 3rd-trimester weights (-9.0 to -11.6 kg). Weight loss was higher among women without excessive gestational weight gain (GWG) (-2.7 to -9.7 kg) than those with excessive GWG (2.3 to -1.8 kg), resulting in postnatal weight measurements lower than their 1st trimester. These pilot data suggest preconception interventions should commence in pregnancy with a focus on GWG, and postnatal women need early support to achieve guideline-recommendations for diet and PA. Further research in a larger population could inform preconception intervention strategies to tackle inequalities in maternal obesity and subsequent pregnancy outcomes.

The long-term effectiveness and cost-effectiveness of public health interventions; how can we model behavior? A review.

The effectiveness and cost of a public health intervention is dependent on complex human behaviors, yet health economic models typically make simplified assumptions about behavior, based on little theory or evidence. This paper reviews existing methods across disciplines for incorporating behavior within simulation models, to explore what methods could be used within health economic models and to highlight areas for further research. This may lead to better-informed model predictions. The most promising methods identified which could be used to improve modeling of the causal pathways of behavior-change interventions include econometric analyses, structural equation models, data mining and agent-based modeling; the latter of which has the advantage of being able to incorporate the non-linear, dynamic influences on behavior, including social and spatial networks. Twenty-two studies were identified which quantify behavioral theories within simulation models. These studies highlight the importance of combining individual decision making and interactions with the environment and demonstrate the importance of social norms in determining behavior. However, there are many theoretical and practical limitations of quantifying behavioral theory. Further research is needed about the use of agent-based models for health economic modeling, and the potential use of behavior maintenance theories and data mining.

Natural experiments for the evaluation of place-based public health interventions: a methodology scoping review.

Introduction: Place-based public health evaluations are increasingly making use of natural experiments. This scoping review aimed to provide an overview of the design and use of natural experiment evaluations (NEEs), and an assessment of the plausibility of the as-if randomization assumption. Methods: A systematic search of three bibliographic databases (Pubmed, Web of Science and Ovid-Medline) was conducted in January 2020 to capture publications that reported a natural experiment of a place-based public health intervention or outcome. For each, study design elements were extracted. An additional evaluation of as-if randomization was conducted by 12 of this paper's authors who evaluated the same set of 20 randomly selected studies and assessed 'as-if ' randomization for each. Results: 366 NEE studies of place-based public health interventions were identified. The most commonly used NEE approach was a Difference-in-Differences study design (25%), followed by before-after studies (23%) and regression analysis studies. 42% of NEEs had likely or probable as-if randomization of exposure (the intervention), while for 25% this was implausible. An inter-rater agreement exercise indicated poor reliability of as-if randomization assignment. Only about half of NEEs reported some form of sensitivity or falsification analysis to support inferences. Conclusion: NEEs are conducted using many different designs and statistical methods and encompass various definitions of a natural experiment, while it is questionable whether all evaluations reported as natural experiments should be considered as such. The likelihood of as-if randomization should be specifically reported, and primary analyses should be supported by sensitivity analyses and/or falsification tests. Transparent reporting of NEE designs and evaluation methods will contribute to the optimum use of place-based NEEs.

Exploratory analysis of reflective, reactive, and homeostatic eating behaviour traits on weight change during the 18-month NoHoW weight maintenance trial.

Behaviour change interventions for weight management have found varied effect sizes and frequent weight re-gain after weight loss. There is interest in exploring whether differences in eating behaviour can be used to develop tailored weight management programs. This secondary analysis of an 18-month weight maintenance randomised controlled trial (RCT) aimed to investigate the association between individual variability in weight maintenance success and change in eating behaviour traits (EBT). Data was analysed from the NoHoW trial (Scott et al., 2019), which was designed to measure processes of change after weight loss of ≥5% body weight in the previous year. The sample included 1627 participants (mean age = 44.0 years, SD = 11.9, mean body mass index (BMI) = 29.7 kg/m2, SD = 5.4, gender = 68.7% women/31.3% men). Measurements of weight (kg) and 7 EBTs belonging to domains of reflective, reactive, or homeostatic eating were taken at 4 time points up to 18-months. Increases in measures of 'reactive eating' (binge eating, p < .001), decreases in 'reflective eating' (restraint, p < .001) and changes in 'homeostatic eating' (unlimited permission to eat, p < .001 and reliance on hunger and satiety cues, p < .05) were significantly and independently associated with concomitant weight change. Differences in EBT change were observed between participants who lost, maintained, or re-gained weight for all EBTs (p < .001) except for one subscale of intuitive eating (eating for physical reasons, p = .715). Participants who lost weight (n = 322) exhibited lower levels of reactive eating and higher levels of reflective eating than participants who re-gained weight (n = 668). EBT domains can identify individuals who need greater support to progress in weight management interventions. Increasing reflective eating and reducing reactive eating may enhance weight management success.

Preventing type 2 diabetes: A research agenda for behavioural science.

AIMS: The aim of this narrative review was to identify important knowledge gaps in behavioural science relating to type 2 diabetes prevention, to inform future research in the field. METHODS: Seven researchers who have published behaviour science research applied to type 2 diabetes prevention independently identified several important gaps in knowledge. They met to discuss these and to generate recommendations to advance research in behavioural science of type 2 diabetes prevention. RESULTS: A total of 21 overlapping recommendations for a research agenda were identified. These covered issues within the following broad categories: (a) evidencing the impact of whole population approaches to type 2 diabetes prevention, (b) understanding the utility of disease-specific approaches to type 2 diabetes prevention such as Diabetes Prevention Programmes (DPPs) compared to generic weight loss programmes, (c) identifying how best to increase reach and engagement of DPPs, whilst avoiding exacerbating inequalities, (d) the need to understand mechanism of DPPs, (e) the need to understand how to increase maintenance of changes as part of or following DPPs, (f) the need to assess the feasibility and effectiveness of alternative approaches to the typical self-regulation approaches that are most commonly used, and (g) the need to address emotional aspects of DPPs, to promote effectiveness and avoid harms. CONCLUSIONS: There is a clear role for behavioural science in informing interventions to prevent people from developing type 2 diabetes, based on strong evidence of reach, effectiveness and cost-effectiveness. This review identifies key priorities for research needed to improve existing interventions.

Beyond Individual Cognitions: Time for Intervention Science to Focus on Health Context and Audience.

Intervention science faces a hazardous paradox: on the one hand, vulnerable populations (eg, patients, people from low socioeconomic background, older adults) are those for whom adoption of healthy behaviors is most urgent; on the other hand, behavior change models are less predictive, and interventions less successful, in these populations. This commentary presents 4 reasons that may explain this issue: (1) research mostly focuses on what causes behavior and how to change it, at the expense of investigating among whom and under what conditions models are valid; (2) models put an undue emphasis on individual cognitions; (3) most studies are not conducted on vulnerable populations; and (4) most researchers are from high-income countries. Several avenues are proposed to address this issue: (1) providing a central place to the context and audience in health behavior change modelization, through collaborations with researchers from other disciplines and countries, and with members of the targeted audience; (2) better reporting samples' sociodemographic characteristics and increasing samples' diversity; and (3) using more rigorous and innovative designs (eg, powered randomized controlled trials, N-of-1 trials, intensive longitudinal studies). In conclusion, it becomes urgent to change the way we do research: the social utility and credibility of intervention science depend on it.

Long-Term Effect of Weight Regain Following Behavioral Weight Management Programs on Cardiometabolic Disease Incidence and Risk: Systematic Review and Meta-Analysis.

BACKGROUND: Behavioral weight management programs (BWMPs) enhance weight loss in the short term, but longer term cardiometabolic effects are uncertain as weight is commonly regained. We assessed the impact of weight regain after BWMPs on cardiovascular risk factors, diabetes, and cardiovascular disease. METHODS: Trial registries, 11 databases, and forward-citation searching (latest search, December 19) were used to identify articles published in English, from any geographical region. Randomized trials of BWMPs in adults with overweight/obesity reporting cardiometabolic outcomes at ≥12 months at and after program end were included. Differences between more intensive interventions and comparator groups were synthesized using mixed-effects, meta-regression, and time-to-event models to assess the impact of weight regain on cardiovascular disease incidence and risk. RESULTS: One hundred twenty-four trials reporting on ≥1 cardiometabolic outcomes with a median follow-up of 28 (range, 11-360) months after program end were included. Median baseline participant body mass index was 33 kg/m2; median age was 51 years. Eight and 15 study arms (7889 and 4202 participants, respectively) examined the incidence of cardiovascular disease and type 2 diabetes, respectively, with imprecise evidence of a lower incidence for at least 5 years. Weight regain in BWMPs relative to comparators reduced these differences. One and 5 years after program end, total cholesterol/HDL (high-density lipoprotein) ratio was 1.5 points lower at both times (82 studies; 19 003 participants), systolic blood pressure was 1.5 mm mercury and 0.4 mm lower (84 studies; 30 836 participants), and HbA1c (%) 0.38 lower at both times (94 studies; 28 083 participants). Of the included studies, 22% were judged at high risk of bias; removing these did not meaningfully change results. CONCLUSIONS: Despite weight regain, BWMPs reduce cardiometabolic risk factors with effects lasting at least 5 years after program end and dwindling with weight regain. Evidence that they reduce the incidence of cardiovascular disease or diabetes is less certain. Few studies followed participants for ≥5 years. REGISTRATION: URL: https://www.crd.york.ac.uk/PROSPERO/; Unique identifier: CRD42018105744.