Dr Zoe Kolokotroni

The selective non-peptide NK1 receptor antagonist NKP608 has been shown to exert potent anxiolytic-like effects in the rat and gerbil social interaction tests. In vitro binding of NKP608 in cortical, striatal and rest-of-brain tissue samples from mice, rats and gerbils indicated comparable pIC50 values for rats and mice (in all three tissues) and only slightly higher values for gerbils. It would therefore be expected that doses previously found to produce anxiolytic-like effects in rats and gerbils would also be active in mice. The present study evaluated NKP608 in one of the most widely-used animal models of anxiety, the mouse elevated plus-maze. Two consecutive experiments were conducted in which the effects of NKP608 (0.0003-10.0 mg/kg, p.o.) were compared to those produced by the prototypical benzodiazepine anxiolytic, chlordiazepoxide (CDP, 15 mg/kg, p.o.). Ethological scoring methods were used to provide comprehensive behavioural profiles for each compound. In both experiments, acute CDP treatment resulted in significant anxioselective effects, i.e., reductions in measures of open arm avoidance without any alteration in general activity levels (closed arm entries and rearing). Although the results of Experiment 1 (0.001-10.0 mg/kg NKP608) suggested a weak anxiolytic-like action of NKP608 at 0.001 mg/kg (significant increase in percent open arm entries), Experiment 2 failed both to replicate this effect or to find any behavioural activity at lower (0.0003 mg/kg) or higher (0.03 mg/kg) doses. Present findings suggest that the anxiolytic efficacy of this NK1 receptor antagonist may be test-specific and thus limited to particular subtypes of anxiety. These new data are also discussed in relation to the general difficulty of relating the behavioural profiles of NK1 receptor antagonists to their potency at NK1 receptors. © 2004 Elsevier B.V. All rights reserved.

Introduction: Understanding an individual’s vulnerability to drug addiction has important implications for the development of effective personal treatment plans. Although theories acknowledge impulsive behaviour as a key component of drug addiction, little is known about the influence of trait impulsivity on an individual’s susceptibility to the effects of psychostimulants on impulsivity at critical phases of the addiction cycle. Methods: This study investigated the short and longer-term effects of chronic nicotine administration on impulsive choice in rats selected for high (HI) and low impulsivity (LI) on a delay discounting task. Rats prepared with subcutaneously osmotic mini-pumps received either nicotine (3.16 mg/kg/day [freebase]) or saline for 7 days. Performance was assessed during chronic treatment, early and late withdrawal, and in response to acute nicotine challenges following prolonged abstinence. Results: Chronic nicotine increased impulsive choice in LI but not HI animals. Spontaneous withdrawal was associated with a nicotine abstinence syndrome, the early stages of which were characterised by opposing effects on impulsive choice in HI and LI animals. A transient decrease in impulsivity was observed in HI animals whilst the LI group remained more impulsive for up to 1 week following drug termination. Following normalisation of behaviour, acute nicotine challenges (0.125, 0.25, 0.5 mg/kg, SC) markedly increased impulsive choice regardless of trait impulsivity and drug history. Conclusion: The results indicate that only LI individuals are vulnerable to chronic drug- and withdrawal-induced impairments in self-control which may increase the likelihood of the transition to, and maintenance of, nicotine dependence.

Rationale Drug addiction is a chronically relapsing disorder characterised by compulsive drug use and loss of control over drug intake. Although several theories propose impulsivity as a key component of addiction, the precise nature of this relationship remains unclear. Objectives This study aims to investigate the short- and longer-term effects of chronic nicotine administration on behavioural inhibition. Methods Rats were trained on a symmetrically reinforced go/no-go task, following which they were subcutaneously prepared with osmotic minipumps delivering either nicotine (3.16 mg kg−1 day−1 (freebase)) or saline for 7 days. Performance was assessed daily during chronic treatment, in early and late abstinence, and in response to acute nicotine challenges following prolonged abstinence. Results Chronic nicotine resulted in a transient reduction in inhibitory control. Spontaneous withdrawal was associated with a nicotine abstinence syndrome, the early stages of which were characterised by a significant increase in inhibitory control. This was, however, short-lived with a decrease in inhibition observed in the second week of abstinence. Whilst performance returned to baseline by the end of the third week, acute challenges (0.125, 0.25, 0.5 mg/kg, SC) revealed that nicotine exposure had sensitised animals to the disinhibitory effects of the compound. Conclusions Drug-induced loss of inhibitory control may be critically involved both in the initial and later stages of addiction. Neuroadaptations occurring during chronic exposure to and/or withdrawal from nicotine render animals more sensitive to the disinhibitory effects of the drug. Longer-term changes in behaviour may play an important role in the increased susceptibility to relapse in those with a history of nicotine abuse.

RATIONALE: Heavy smokers exhibit greater levels of impulsive choice and behavioural disinhibition than non-smokers. To date, however, the relationship between nicotine use and differing dimensions of impulsivity has not been systematically assessed. OBJECTIVES: A series of studies was designed to assess the acute dose-response effects of nicotine and the nicotinic receptor antagonist mecamylamine alone, and in combination with nicotine, on impulsive choice and behavioural disinhibition in rats. METHODS:Separate groups of rats were trained on a symmetrically reinforced go/no-go task to measure levels of disinhibition and a systematic delayed reward task to measure levels of impulsive choice. Once trained, all animals in each task were treated acutely with nicotine (0.125, 0.25, 0.5 and 1.0 mg/kg), mecamylamine (0.1, 0.3 and 1.0 mg/kg) and varying doses of mecamylamine (0.1, 0.3 and 1.0 mg/kg) prior to nicotine (0.5 mg/kg). An additional experiment assessed the effects of alterations in primary motivation (presatiation and fasting) on performance in both tasks. RESULTS: Acute nicotine increased both impulsive choice and behavioural disinhibition, effects that were blocked by pre-treatment with mecamylamine. Mecamylamine when administered alone did not alter impulsive behaviour. The lack of effect of presatiation on performance measures suggests that the observed nicotine-induced impulsivity cannot be attributed to the anorectic activity of the compound. CONCLUSIONS:Present findings support the hypothesis that heightened impulsivity in smokers may in part be a consequence of the direct acute effects of nicotine. As such, drug-induced changes in impulsivity may play a critical role in the transition to and maintenance of nicotine dependence.

Rationale: Drug addiction is a chronically relapsing disorder characterised by compulsive drug use and loss of control over drug intake. Although several theories propose impulsivity as a key component of addiction, the precise nature of this relationship remains unclear. Objectives: This study aims to investigate the short- and longer-term effects of chronic nicotine administration on behavioural inhibition. Methods: Rats were trained on a symmetrically reinforced go/no-go task, following which they were subcutaneously prepared with osmotic minipumps delivering either nicotine (3.16 mg kg−1 day−1 (freebase)) or saline for 7 days. Performance was assessed daily during chronic treatment, in early and late abstinence, and in response to acute nicotine challenges following prolonged abstinence. Results: Chronic nicotine resulted in a transient reduction in inhibitory control. Spontaneous withdrawal was associated with a nicotine abstinence syndrome, the early stages of which were characterised by a significant increase in inhibitory control. This was, however, short-lived with a decrease in inhibition observed in the second week of abstinence. Whilst performance returned to baseline by the end of the third week, acute challenges (0.125, 0.25, 0.5 mg/kg, SC) revealed that nicotine exposure had sensitised animals to the disinhibitory effects of the compound. Conclusions: Drug-induced loss of inhibitory control may be critically involved both in the initial and later stages of addiction. Neuroadaptations occurring during chronic exposure to and/or withdrawal from nicotine render animals more sensitive to the disinhibitory effects of the drug. Longer-term changes in behaviour may play an important role in the increased susceptibility to relapse in those with a history of nicotine abuse.

In this paper, we trained people to produce 90° mean relative phase using task-appropriate feedback and investigated whether and how that learning transfers to other coordinations. Past work has failed to find transfer of learning to other relative phases, only to symmetry partners (identical coordinations with reversed lead-lag relationships) and to other effector combinations. However, that research has all trained people using transformed visual feedback (visual metronomes, Lissajous feedback) which removes the relative motion information typically used to produce various coordinations (relative direction, relative position; Wilson & Bingham, 2008) . Coordination feedback (Wilson, Snapp-Childs, Coats, & Bingham, 2010) preserves that information and we have recently shown that relative position supports transfer of learning between unimanual and bimanual performance of 90° (Snapp-Childs, Wilson, & Bingham, 2015). Here we ask whether that information can support the production of other relative phases. We found large, asymmetric transfer of learning bimanual 90° to bimanual 60° and 120°, supported by perceptual learning of relative position information at 90°. For learning to transfer, the two tasks must overlap in some critical way; this is additional evidence that this overlap must be informational. We discuss the results in the context of an ecological, task dynamical approach to understanding the nature of perception-action tasks.

Research has largely focused on how attentional bias to smoking-related cues and impulsivity independently influence the development and maintenance of cigarette smoking, with limited exploration of the relationship between these mechanisms. The current experiments systematically assessed relationships between multiple dimensions of impulsivity and attentional bias, at different stages of attention, in smokers varying in nicotine dependency and deprivation. Nonsmokers (NS; n = 26), light-satiated smokers (LS; n = 25), heavy-satiated smokers (HS; n = 23) and heavy 12-hour nicotine-deprived smokers (HD; n = 30) completed the Barratt Impulsivity Scale, delayed discounting task, stop-signal task, information sampling task and a visual dot-probe assessing initial orientation (200 ms) and sustained attention (2000 ms) toward smoking-related cues. Sustained attention to smoking-related cues was present in both HS and LS, while initial orientation bias was only evident in HS. HS and LS also had greater levels of trait motor and nonplanning impulsivity and heightened impulsive choice on the delay discounting task compared with NS, while heightened trait attentional impulsivity was only found in HS. In contrast, in HD, nicotine withdrawal was associated with no attentional bias but heightened reflection impulsivity, poorer inhibitory control and significantly lower levels of impulsive choice relative to satiated smokers. Trait and behavioral impulsivity were not related to the extent of attentional bias to smoking-related cues at any stage of attention, level of nicotine dependency or state of deprivation. Findings have both clinical and theoretical implications, highlighting the unique and independent roles impulsivity and attentional bias may play at different stages of the nicotine addiction cycle.

Research spanning 100 years has revealed that learning a novel perception-action task is remarkably task-specific. With only a few exceptions, transfer is typically very small, even with seemingly small changes to the task. This fact has remained surprising given previous attempts to formalise the notion of what a task is, which have been dominated by common-sense divisions of tasks into parts. This article lays out an ecologically grounded alternative, ecological task dynamics, which provides us with tools to formally define tasks as experience from the first-person perspective of the learner. We explain this approach using data from a learning and transfer experiment using bimanual coordinated rhythmic movement as the task, and acquiring a novel coordination as the goal of learning. 10 participants were extensively trained to perform 60° mean relative phase; this learning transferred to 30° and 90°, against predictions derived from our previous work. We use recent developments in the formal model of the task to guide interpretation of the learning and transfer results.

In this paper, we trained people to produce 90° mean relative phase using task-appropriate feedback and investigated whether and how that learning transfers to other coordinations. Past work has failed to find transfer of learning to other relative phases, only to symmetry partners (identical coordinations with reversed lead-lag relationships) and to other effector combinations. However, that research has all trained people using transformed visual feedback (visual metronomes, Lissajous feedback) which removes the relative motion information typically used to produce various coordinations (relative direction, relative position; Wilson and Bingham, in Percept Psychophys 70(3):465-476, 2008). Coordination feedback (Wilson et al., in J Exp Psychol Hum Percept Perform 36(6):1508, 2010) preserves that information and we have recently shown that relative position supports transfer of learning between unimanual and bimanual performance of 90° (Snapp-Childs et al., in Exp Brain Res 233(7), 2225-2238, 2015). Here, we ask whether that information can support the production of other relative phases. We found large, asymmetric transfer of learning bimanual 90° to bimanual 60° and 120°, supported by perceptual learning of relative position information at 90°. For learning to transfer, the two tasks must overlap in some critical way; this is additional evidence that this overlap must be informational. We discuss the results in the context of an ecological, task dynamical approach to understanding the nature of perception-action tasks.

Previous work has investigated the information-based mechanism for learning and transfer of learning in coordinated rhythmic movements. In those papers, we trained young adults to produce either 90° or 60° and showed in both cases that learning entailed learning to use relative position as information for the relative phase. This variable then supported transfer of learning to untrained coordinations +/30° on either side. In this article, we replicate the 90° study with younger adults and extend it by training older adults (aged between 55 and 65 years). Other work has revealed a steep decline in learning rate around this age, and no follow-up study has been able to successfully train older adults to perform a novel coordination. We used a more intensive training paradigm and showed that while older adult learning rates remain about half that of younger adults, given time they are able to acquire the new coordination. They also learn to use relative position, and consequently show the same pattern of transfer. We discuss implications for attempts to model the process of learning in this task.

Abstract

Background Young adulthood is a critical period where there is an increased weight gain trajectory. Understanding the weight management support needs of young adults with excess weight is essential to enable the delivery of appropriate and tailored services and prevent the development of comorbidities. This study sought to determine the current health service usage, weight management practices and support needs, in young adults with excess weight. Methods A mixed-methods convergent parallel design was employed. A cohort of community-dwelling young adults (18–35 years), with excess weight (BMI ≥ 25), residing in the UK and Australia participated in an online, longitudinal survey. Cross-sectional data was analysed descriptively, including quantitative measures of health service usage and weight management practices. Responses to an open-ended question asking what support participants would find most helpful were analysed using Thematic Template Analysis. Convergence and divergence across sociodemographic characteristics were explored. Results The sample (n = 410) included 204 women, 201 men and five non-binary people with a mean age of 28.3 and BMI of 35.8. Most participants reported a white ethnicity (80%) and resided in the UK (83%). Half reported a below median gross household income (49%). Most (73%) reported currently trying to manage their weight and 63% were using commercial weight management products or self-directed diets. Only 12% of participants reported accessing healthcare services for weight management support or treatment, yet qualitative responses indicated a desire for support from a dietitian or psychologist. Five themes indicated a need for structured but tailored resources, simplicity, addressing internal and external barriers, access to holistic professional support, and access to networks vs a preference for self-reliance. Conclusions Young adults with excess weight are using commercial products and self-led diets but many desire specialist healthcare professionals to support their weight management. Young adults appear to prefer online resources and support that are simplistic, structured and individually tailored to their diverse cultural preferences, routines, environments, and comorbidities. Furthermore, findings indicate unmet psychological support needs amongst young adults with excess weight in the UK and Australia. Protocol Whatnall, M., Fozard, T., Kolokotroni, K.Z., Marwood, J., Evans, T., Ells, L.J. and Burrows, T., 2022. Understanding eating behaviours, mental health and weight change in young adults: protocol paper for an international longitudinal study. BMJ open, 12(9), p.e064963.

Most research on capacity to consent to substance-involved sex has focused exclusively on the implications of alcohol with little attention given to other or additional psychoactive drugs. This study aimed to explore people’s understanding and experiences of the capacity to consent to alcohol- and/or drug-involved sexual activity. UK adults (N = 354) completed an online mixed-methods survey on sexual consent during sober, alcohol- and/or drug-involved sex. Qualitative data were analyzed using thematic analysis. Themes for capacity to consent were: (1) ‘There is no normative understanding of substance-involved sexual consent’, (2) ‘Moving beyond the binary of consciousness versus incapacitation’ and (3) ‘Substance-involved sexual decisions are viewed as irresponsible’. The findings illustrated that capacity to consent is nuanced and multidimensional, and that people’s understandings and experiences of capacity to consent to substance-involved sex are not solely individual, but rather, they are also shaped by their environment. We call for a multidimensional view of capacity to consent, where a standard of ‘unimpaired’, rather than sober, is used and modeled by academics, legislators, and educators.

Sexual consent is a central component in the primary prevention of sexual violence. There is growing evidence of the impact that alcohol consumption has on sexual consent. However, there has been no review examining sexual consent in the context of other drug-taking. Published literature was sought using searches of: PsycINFO, PsycARTICLES, Scopus, Web of Science, CINAHL, MEDLINE and Open Dissertations. Unpublished literature, such as unpublished government or charity reports, were identified through Google search engine. All 21 eligible studies employed qualitative or mixed methods; therefore, a thematic synthesis was deemed an appropriate method of analysis. Three themes were constructed: “Drug-taking changes sexual norms”, “Drug-taking diminishes the capacity to make sexual decisions” and “Drug-taking reduces verbal and non-verbal ability to communicate consent”. The findings demonstrated that prevailing models of sexual consent may not account for circumstances relevant to drug-involved sex, such as how drug-taking impacts freedom and capacity to consent to sex. We propose the use of the medical model of capacity to consent as a broader framework through which capacity to consent to sex in drug-taking contexts can be assessed. The importance of both the social and situational context for sexual decision-making following drug-taking is discussed.

Sexual consent is highly topical and currently sits at the forefront of media, educational and government campaigns; education regarding sexual consent communication is considered to be one of the key ways that we can reduce instances of sexual violence in the general population. Despite intoxication being one barrier to giving/ gaining sexual consent, there is a lack of research which examines how the voluntary use of drugs aside from alcohol affect sexual consent communication compared to when sober or when alcohol has been used (on its own). For example, how do individuals indicate to their sexual partner(s) that they are willing to have a sexual experience or how do they interpret the willingness of their sexual partner(s) after taking drugs? Additionally, there is a lack of information on how feelings of sexual wantedness (i.e. desire) and willingness are influenced by drug use. The findings could inform drug-users about how their substance use impacts their sexual experiences, notably, their ability to freely give (or not give) sexual consent. Preliminary data from an online cross-sectional survey of 18- to 40-year-old, sexually active, UK women’s and men’s sexual experiences when sober, under the influence of alcohol, drugs, or the combined effects of alcohol and drugs, will be presented. This poster explores how women’s sexual consent practises are different or similar across sober, alcohol-involved and drug-involved sexual experiences and feelings of sexual wantedness and willingness during sober, alcohol-involved and drug-involved sexual experiences. Implications for sexual consent policies and sexual violence prevention will be discussed.

Despite a number of individuals engaging in sexual experiences following voluntary alcohol and/or drug use, there has been a lack of research examining how (if at all) getting/giving sexual consent is different or similar following the use of alcohol and/or other drugs in comparison to when sober. This presentation discusses preliminary data from an online research project of 18- to 40-year-old UK men and women’s sexual experiences when sober, after drinking alcohol and/or after using drugs. In particular, the impact of drug and alcohol use on sexual consent communication and feelings of sexual wantedness and willingness will be discussed, along with implications for sexual consent policies and sexual violence prevention.

Sexual violence is a significant public health problem. Approximately 473,000 individual’s experience sexual assault (SA) each year in England and Wales (Ministry of Justice, 2013). Although sexual orientation is often overlooked in population-based surveys, sexual minority groups reportedly experience greater levels of SA in comparison to heterosexual counterparts (Hequembourg, Parks & Hughes, 2015; Walters & Breiding, 2013). High levels of drug use are also observed within sexual minority groups; drugs such as gamma-hydroxybutyrate, ketamine and mephedrone are reported to be frequently used among gay and bisexual men (Bourne et al, 2014). The relationship between substance use and SA is well supported in the literature; evidence suggests the acute voluntary use of a psychoactive substance may heighten the risk for sexual assault (e.g. due to a perpetrators increased ability to exploit incapacitated individuals; Jessell, Mateu-Gelabert & Friedman, 2015). With reportedly high levels of both drug use and SA, sexual minority groups may be more likely to experience SA whilst under the influence of an illicit drug compared to heterosexual populations. To date, there is a lack of research which has examined this. This poster will present pilot study data from an online cross-sectional survey examining sexual experiences that took place when sober, under the influence of alcohol, drugs, or the combined effect of alcohol and drugs. Participants were sexually active, males and females, aged 18 – 40, residing in the North of England. Results are discussed with regards to sexual assault experiences, drug and alcohol use, gender and sexuality.

INTRODUCTION: Incentive Sensitisation theory suggests wanting and liking are dissociable concepts, with wanting, but not liking typically increasing with repeated drug use. Wanting is associated with anticipation of reward, whereas liking relates to pleasure derived from consummatory behaviour. However, numerous studies have conceptualised liking as an anticipatory cognition. This study explores whether levels of nicotine dependence differentially effect wanting and liking responses to smoking-related cues, and whether anticipated and consummatory liking are equivalent, and dissociable from wanting. METHOD: Heavy (HS, mean = 16 cigarettes/day) and light non-daily (LS, mean = 2 cigarettes/day) smokers completed wanting and anticipated liking questionnaires pre-, immediately post-exposure to smoking-related and neutral cues and at session-end. Consummatory liking was measured post-session, immediately after smoking. RESULTS: Wanting and anticipated liking responses were comparable. Smoking-related cues increased wanting and anticipated liking compared to neutral cues. This effect was maintained until session-end. No baseline differences were seen between HS and LS on wanting or anticipated liking, however after cue exposure, and at session-end, HS reported greater drug wanting and anticipated liking than LS. Conversely, HS and LS did not differ on consummatory liking. Analyses confirmed the relationship between wanting and anticipated liking was significantly stronger than wanting and consummatory liking or anticipated and consummatory liking. CONCLUSIONS: Wanting and anticipated liking appear to be overlapping constructs assessing expectations of reward, that are dissociable from consummatory liking. Furthermore, heavier smoking increases drug wanting, but not smoking pleasure. Future attempts to dissociate these concepts should ensure liking is measured during/immediately after consumption.

BACKGROUND: Cannabis smoking and cigarette smoking often co-occur, yet limited research has investigated the potentially different role impulsivity may play when these behaviours occur in isolation, compared with in combination. AIMS: This study examined trait and behavioural impulsivity as a function of both cigarette and cannabis smoking. METHODS: Trait impulsivity (BIS-11) was compared between 44 non-smokers, 76 cigarette only, 47 cannabis only and 58 cannabis plus cigarette smokers. The effects of cigarette and cannabis smoking on behavioural impulsivity (stop-signal and information sampling tasks) were then assessed in 87 of these participants during a laboratory session. RESULTS: Trait impulsivity was significantly higher in cigarette smokers than non-smokers, irrespective of cannabis use, except for motor impulsivity, where cigarette smoking was only associated with elevated trait impulsivity in non-smokers of cannabis. Dimensions of trait impulsivity were significantly positively related to cigarette smoking frequency and nicotine dependence, but not to cannabis smoking frequency or dependence. Smoking cigarettes or cannabis was associated with significantly impaired reflection impulsivity relative to not smoking either substance. However, no additional increases in reflection impulsivity were observed in those who smoked both cigarettes and cannabis. No group differences in response inhibition were detected. CONCLUSIONS: Heightened trait impulsivity appears to be uniquely related to cigarette smoking, whilst the smoking of cigarettes or cannabis is associated with impairments in reflection impulsivity. Improved outcomes for treating cannabis dependence may result from encouraging concomitant cigarette smokers to cease using both drugs simultaneously in order to reduce heightened impulsivity and risk of relapse.

There is limited research on how substance use impacts people’s freedom to negotiate sexual activity with others, particularly in distinguishing between alcohol and drug use. This study addressed that gap by exploring how substance use can both extend and constrain sexual negotiation. A mixed-methods online survey of 354 UK adults aged 18–40 examined sexual consent across sober, alcohol-, and drug-involved experiences. This paper focuses on the qualitative data for substance-involved sex only. Three themes were constructed from the data using Reflexive Thematic Analysis: (1) Substance use can facilitate sexual negotiation with others; (2) Substance use opens up new sexual opportunities; (3) Sexual refusal is constrained by relational and event-based influences. Participants described how drugs such as MDMA and cannabis enhanced mutuality and communication, sometimes disrupting traditional sexual scripts. However, gendered power dynamics, social pressures, and time and event-based constraints continued to limit sexual refusal, especially for women. These findings suggest that while drug use can involve ethical and consensual sexual experiences, it can also reinforce existing inequalities. Further research is needed to explore how different drugs, and social contexts, shape (un)ethical substance-involved sexual behavior.

Background Accurate anthropometric measurement is important within epidemiological studies and clinical practice. Traditionally, self-reported weight is validated against in-person weight measurement. Objectives This study aimed to 1) determine the comparison of online self-reported weight against images of weight captured on scales in a young adult sample, 2) compare this across body mass index (BMI), gender, country, and age groups, and 3) explore demographics of those who did/did not provide a weight image. Methods Cross-sectional analysis of baseline data from a 12-mo longitudinal study of young adults in Australia and the UK was conducted. Data were collected by online survey via Prolific research recruitment platform. Self-reported weight and sociodemographics (for example, age, gender) were collected for the whole sample (n = 512), and images of weight for a subset (n = 311). Tests included Wilcoxon signed-rank test to evaluate differences between measures, Pearson correlation to explore the strength of the linear relationship, and Bland-Altman plots to evaluate agreement. Results Self-reported weight [median (interquartile range), 92.5 kg (76.7–112.0)] and image-captured weight [93.8 kg (78.8–112.8)] were significantly different (z = −6.76, P < 0.001), but strongly correlated (r = 0.983, P < 0.001). In the Bland-Altman plot [mean difference −0.99 kg (−10.83, 8.84)], most values were within limits of agreement (2 standard deviation). Correlations remained high across BMI, gender, country, and age groups (r > 0.870, P < 0.002). Participants with BMI in ranges 30–34.9 and 35–39.9 kg/m2 were less likely to provide an image. Conclusions This study demonstrates the method concordance of image-based collection methods with self-reported weight in online research.

Summary Background There is limited evidence and clinical guidelines on the behavior change support required for low‐calorie diet programs. This systematic review aimed to establish the behavior change technique(s) (BCT) implemented in weight loss interventions (≤1200 kcal/d) and how these contribute to effectiveness. Methods Databases were searched from inception to April 2022. Screening, data extraction, BCT coding, and quality appraisal were conducted in duplicate using the Template for Intervention Description and Replication framework, Behavior Change Technique Taxonomy, and Cochrane Risk of Bias 2 tool. Data were analyzed via narrative synthesis and random effects multi‐level meta‐analyses. Results Thirty‐two papers reporting on 27 studies were included. Twenty‐four BCTs were identified across studies. Eight BCTs were significantly associated with a larger reduction in weight at the end‐of‐diet time‐point; one BCT was statistically significant at the end of weight maintenance. Physical activity, Type 2 Diabetes, and BMI category moderated intervention effects. Conclusions and implications This is the first meta‐analysis to examine how specific BCTs contribute to the effectiveness of low‐calorie diets. It is recommended that a) these findings are used to develop clinical guidelines specific to behavioral support in low‐calorie diet programs, and b) program commissioners stipulate the use of these BCTs in their service specifications.

Introduction Understanding the complexities of change in eating behaviours, mental health, well-being and weight is crucial to inform healthcare and service provision, particularly in light of the exacerbating effects of the COVID-19 pandemic. This study aims to address the need for more comprehensive cross-sectional and longitudinal evidence, by tracking eating behaviours, mental health, health related behaviours and weight over a 12-month period, in a sample of young adults (18–35 years) in the UK and Australia. Methods and analysis Online surveys administered via the Prolific online research platform will be used for data collection at baseline, 6 months and 12 months. The survey (approximately 45 min) measures demographics, the impact of COVID-19, body mass index (BMI), weight management and health service usage, eating behaviours, personality, mental health, and health-related behaviours. An optional substudy component at each time point aims to validate self-reported weight in the main survey through images. Study inclusion criteria are; aged 18–34 years at baseline, BMI ≥20 kg/m2, and residing in the UK or Australia. A target of 500 participants at baseline was set, recruited through Prolific, and with recruitment stratified by BMI, sex and country. The proposed analyses include creating static predictive models using baseline data (eg, using latent class analysis, factor analysis or similar), and mapping changes longitudinally (eg, using multivariate regressions). These analyses will enable changes in the study measures to be identified, as well as predictors and outcomes of change. Ethics and dissemination Ethical approval was granted by Leeds Beckett University, UK (reference number 86004) and the University of Newcastle, Australia (reference number H-2022–0110). Study findings will be disseminated through scientific journals, conferences, institute websites and social media, and briefings tailored to policy, practice and the public, with the intention to help inform the future development of health and well-being care and support for young adults across Australia and the UK.