Avoidant Restrictive Food Intake Disorder (ARFID)-Looking beyond the eating disorder lens?

Avoidant Restrictive Food Intake Disorder (ARFID) was first included as a diagnostic category in 2013, and over the past 10 years has been adopted by the international eating disorder community. While greater awareness of these difficulties has increased identification, demand and enabled advocacy for clinical services, the heterogeneous nature of ARFID poses unique challenges for eating disorder clinicians and researchers. This commentary aims to reflect on some of these challenges, focussing specifically on the risk of viewing ARFID through an eating disorder lens. This includes potential biases in the literature as most recent research has been conducted in specialist child and adolescent eating disorder clinic settings, bringing in to question the generalisability of findings to the broad spectrum of individuals affected by ARFID. We also consider whether viewing ARFID predominantly through an eating disorder lens risks us as a field being blinkered to the range of effective skills our multi-disciplinary feeding colleagues may bring. There are opportunities that may come with the eating disorder field navigating treatment pathways for ARFID, including more joined up working with multi-disciplinary colleagues, the ability to transfer skills used in ARFID treatment to individuals with eating disorder presentations, and most notably an opportunity to provide more effective treatment and service pathways for individuals with ARFID and their families. However, these opportunities will only be realised if eating disorder clinicians and researchers step out of their current silos.

A randomised controlled feasibility trial of intermittent theta burst stimulation with an open longer-term follow-up for young people with persistent anorexia nervosa (RaISE): Study protocol.

OBJECTIVE: We present the protocol of a feasibility randomised controlled trial (RCT) of intermittent theta burst stimulation (iTBS) for young people with anorexia nervosa (AN). Effective first-line psychological therapies exist for young people with AN, but little is known about how to treat those who do not respond. Non-invasive neuromodulation, such as iTBS, could address unmet treatment needs by targeting neurocircuitry associated with the development and/or maintenance of AN. DESIGN: Sixty-six young people (aged 13-30 years) with persistent AN will be randomly allocated to receive 20 sessions of real or sham iTBS over the left dorsolateral prefrontal cortex in addition to their usual treatment. Outcomes will be measured at baseline, post-treatment (1-month post-randomisation) and 4-months post-randomisation (when unblinding will occur). Additional open follow-ups will be conducted at 12- and 24-months post-randomisation. The primary feasibility outcome is the proportion of participants retained in the study at 4-months. Secondary outcomes include AN symptomatology, other psychopathology, quality of life, service utilisation, neurocognitive processes, and neuroimaging measures. DISCUSSION: Findings will inform the development of a future large-scale RCT. They will also provide exploratory data on treatment efficacy, and neural and neurocognitive predictors and correlates of treatment response to iTBS in AN.

Management of fraudulent participants in online research: Practical recommendations from a randomized controlled feasibility trial.

OBJECTIVE: Fraudulent participation is an escalating concern for online clinical trials and research studies and can have a significant negative impact on findings. We aim to shed light on the risk and to provide practical recommendations for detecting and managing such instances. METHODS: The FREED-Mobile (FREED-M) study is an online, randomized controlled feasibility trial to assess a digital early intervention for young people (aged 16-25) in England or Wales with eating problems. The trial involved baseline (week 0), post-intervention (week 4), and follow-up (week 12) surveys, alongside weekly modules provided over 4 weeks on the study website. Study completers were compensated with £20 shopping vouchers. Despite the complexity of the trial design, two instances of fraudulent sign-ups occurred in January and March 2023. To counter this, we developed a "fraudulent participants protocol" following internal investigations and discussions with collaborators. RESULTS: The implementation of prevention measures such as reCAPTCHA updates, IP address review, and changes in reimbursement effectively halted further fraudulent sign-ups. Our protocol facilitated the systematic identification and withdrawal of suspected or clear fraudsters and was demonstrably robust at distinguishing between fraudsters and genuine responders. DISCUSSION: All remote, online trials or studies are at risk of fraudulent participation. Drawing from our experience and existing literature, we offer practical recommendations for researchers considering online recruitment and data collection. Vigilance and the integration of deterrents, and data quality checks into the study design from the outset are advised to safeguard research integrity. PUBLIC SIGNIFICANCE: Fraudulent participation in digital research can have asignificant impact on research findings, potentially leading to biased resultsand misinformed decisions. We developed an effective protocol for theprevention, identification, and management of fraudulent participants. Bysharing our insights and recommendations, we hope to raise awareness of thisissue and provide other researchers with the knowledge and strategies necessaryto safeguard research integrity moving forward.

Family body culture, disordered eating and mental health among young adult females during COVID-19.

Different family interactions related to body weight and shape may co-occur and represent a broader 'family body culture'. This may be important in the context of COVID-19 due to a heightened focus on body weight/shape, and many young adults living back with their families. This study aimed to, first, explore relationships between different family body-related interactions to assess the presence of a family body culture, and second, explore relationships between aspects of family body culture, disordered eating and mental health among young adult females during the COVID-19 pandemic. Participants were 233 females aged 18-25 years who completed measures of family body culture (family fat talk; family weight concern; family weight teasing), disordered eating, anxiety and depression. Results showed all aspects of family body culture were significantly, positively related. Engaging in fat talk with family members (self fat talk) was a key correlate of disordered eating, anxiety and depression. Family concern with weight was also significantly associated with disordered eating. Findings suggest that among some families there is a more problematic family body culture with a greater importance placed on body weight and shape through various body-related interactions. Additionally, findings highlight two key aspects of family body culture related to disordered eating and wellbeing among young adult females. Specifically, vocalising critical remarks about one's own body when with family and an environment that may indirectly communicate a high importance of body weight and shape (e.g., via dieting). These should be considered in future family interventions to support healthy eating behaviours.

Individuals with restrictive eating disorders' experience of the introduction of calories on menus in England: An interpretative phenomenological analysis study.

OBJECTIVE: In April 2022 the Calorie Labelling (Out of Home) Regulations came into effect in England where cafés, restaurants, and takeaways with over 250 employees were required to provide calorie labelling on menus. Concerns have been raised regarding the potential negative impact this could have on individuals with eating disorders (EDs), yet this has not been explored using qualitative methodology. METHOD: Eleven participants with a current or previously diagnosed restrictive ED were interviewed in September 2022. Interpretative Phenomenological Analysis (IPA) was used to explore their experience of the introduction of calories on menus. RESULTS: Using IPA we established six themes and seven subordinate themes. These included the introduction of calories on menus as an 'attack' on individuals with EDs; the prominent visual display of calories as an attentional pull; normalising of calories counting; the impact on behaviour; and associated strategies for managing. CONCLUSION: This contributes to research surrounding the implications for public health policies on individuals with EDs, especially their ability to reinforce and amplify disordered thoughts and behaviours, and the need for greater consideration of how to minimise impact and potential harm of large public health campaigns.

Experiences of inpatient eating disorder admissions: A systematic review and meta-synthesis.

OBJECTIVE: There has been a significant increase in the number of inpatient admissions for individuals with eating disorders and, with the most critical cases requiring inpatient treatment, it is essential that we continue to improve associated outcomes. The aim of the study was to synthesise the available qualitative literature on the experiences of inpatient admissions for eating disorders to understand individuals' experiences and identify areas that may require further research and/or service development. METHOD: Searches were performed on the following online databases: PsycINFO, PsycArticles, PsycTherapy MEDLINE, Embase, CINAHL, ASSIA, Scopus and Proquest Open Access Theses. Only papers with qualitative data regarding individuals' experiences of inpatient eating disorder treatment were considered. The CASP qualitative checklist was used to assess studies and relevant data items were extracted. Thematic synthesis was used to integrate the findings in the identified studies. GRADE-CERQual was used to rate the confidence in the findings. RESULTS: Twenty-eight studies were identified which the CASP assessment considered to be adequate. The synthesis produced 5 main themes; 'Care and control', 'Inpatient bubble', 'Being supported and understood', 'Challenges of living with others' eating disorders' and finally 'Relationship to eating disorder'. The GRADE CERQual framework rated findings with high or moderate confidence. CONCLUSIONS: Findings reaffirmed the importance of patient-centred care and the significant impact of being separated from normal life with others also experiencing an eating disorder.

"It's not about wanting to be thin or look small, it's about the way it feels": an IPA analysis of social and sensory differences in autistic and non-autistic individuals with anorexia and their parents.

BACKGROUND: Despite increasing evidence to support an overlap between autism and anorexia nervosa (AN), underlying mechanisms remain poorly understood. Social and sensory factors have emerged as promising targets in both autism and AN, however there remains scope to compare these differences across autistic and non-autistic experiences of AN. Drawing on dyadic multi-perspectives, this study explored experiences of social and sensory differences in autistic and non-autistic adults and their parents and/or carers. METHODS: Using interpretative phenomenological analysis (IPA), dyadic interviews were conducted with 14 dyads, with seven autistic dyads and seven non-autistic dyads. Data analysis was subjected to a triangulation of interpretations: (1) the participants themselves; (2) a neurotypical researcher; (3) and an Autistic researcher with lived/living experience of AN. RESULTS: IPA identified three themes in each group, with similarities and differences between autistic and non-autistic dyads. Similar themes were identified regarding the importance of social connectedness and socio-emotional difficulties, as well a common lack of trust in the social and sensory self and body. Autism-specific themes centred on feelings of social 'defectiveness', disparities between sensing and expressing certain cues, and lifelong, multi-sensory processing differences. Non-autistic themes reflected social comparisons and inadequacy, and sensitivities to the learning of ideals and behaviour through early experiences. CONCLUSIONS: While similarities were observed across both groups, there appeared to be notable differences in the perceived role and influence of social and sensory differences. These findings may have important implications on the delivery and modification of eating disorder interventions. Specifically, they suggest that while treatment targets may look similar, subtle differences in underlying mechanisms and approaches may be required for Autistic individuals with AN across sensory, emotion and communication-based interventions.

A UK-wide survey of healthcare professionals' awareness, knowledge and skills of the impact of food insecurity on eating disorder treatment.

OBJECTIVE: Food insecurity (FI) is associated with significant adverse effects on health and well-being and increasingly recognised as a global problem. The current study explored the impact of FI on eating disorder (ED) clinical practice in the UK, aiming to assess healthcare professionals' (HCPs) knowledge, skills and views on the topic of FI in their patients. DESIGN: This study was an exploratory, mixed-methods, descriptive analysis of online survey data collected from ED HCPs in the UK between September and October 2022. MEASURES: A 15-item survey with rating and open-ended questions was circulated to ED professional organisations in the UK. Descriptive statistics were used to summarise quantitative data, including perceived prevalence of FI in ED clinical practice and confidence in knowledge on the topic. Descriptive content analyses provided insight into perspectives on FI screening and aspects to be included in guidance and resources. RESULTS: 93 ED HCPs completed the survey (40.9 % psychologists). Findings demonstrated healthcare providers' limited knowledge on FI and its relation to EDs, while they increasingly perceive it in their patients, as well as a general lack of available resources on how to address FI in ED treatment. HCPs stressed the need for practical guidance and formal training for dealing with FI in their patients, as well as implementing routine screening. CONCLUSION: These findings provide both important directions for future research and clinical applications related to screening, assessment, treatment and support of food-insecure patients with EDs.

EDIFY (Eating Disorders: Delineating Illness and Recovery Trajectories to Inform Personalised Prevention and Early Intervention in Young People): project outline.

EDIFY (Eating Disorders: Delineating Illness and Recovery Trajectories to Inform Personalised Prevention and Early Intervention in Young People) is an ambitious research project aiming to revolutionise how eating disorders are perceived, prevented and treated. Six integrated workstreams will address key questions, including: What are young people's experiences of eating disorders and recovery? What are the unique and shared risk factors in different groups? What helps or hinders recovery? How do the brain and behaviour change from early- to later-stage illness? How can we intervene earlier, quicker and in a more personalised way? This 4-year project, involving over 1000 participants, integrates arts, design and humanities with advanced neurobiological, psychosocial and bioinformatics approaches. Young people with lived experience of eating disorders are at the heart of EDIFY, serving as advisors and co-producers throughout. Ultimately, this work will expand public and professional perceptions of eating disorders, uplift under-represented voices and stimulate much-needed advances in policy and practice.

Review: Can digital mental health interventions bridge the 'digital divide' for socioeconomically and digitally marginalised youth? A systematic review.

BACKGROUND: Digital mental health interventions (DMHIs) have the potential to improve the efficiency, accessibility and effectiveness of mental health services for young people, with the potential to reach socioeconomically and digitally marginalised young people with mental health needs who would otherwise not seek help in person. This review aims to investigate the characteristics, acceptability and efficacy of DMHIs specifically developed for socioeconomically and digitally marginalised youth. METHOD: Key databases were searched widely and systematically (EMBASE, MEDLINE, PsycINFO, OpenGrey). Final inclusion in this review required studies to evaluate DMHIs specifically targeting socioeconomically and digitally marginalised children and young people through a broad range of research designs. RESULTS: Ten studies, describing seven DHMIs, were included in this review. Studies varied in terms of methodology, population, intervention, outcome measures, technologies used and methodological quality. Qualitative and quantitative results are synthesised across three key phenomena of interest: effectiveness, acceptability and feasibility. Findings suggest that there is moderate but limited evidence supporting DMHIs for improving mental health outcomes among these populations. CONCLUSIONS: While there is moderate evidence suggesting that digitally delivered interventions can be effective in improving mental health outcomes among socioeconomically and digitally marginalised youth, more high-quality research is needed in order to determine whether DMHIs can fully bridge the so-called 'digital divide'.

An 8-month longitudinal exploration of body image and disordered eating in the UK during the COVID-19 pandemic.

Research suggests that the COVID-19 pandemic is negatively impacting mental health, with rates of eating disorder referrals in particular rising steeply during the pandemic. This study aimed to examine 8-month changes in body image and disordered eating during the COVID-19 pandemic, and explore whether any changes were moderated by gender, age, or eating disorder history. This study used a longitudinal survey design in which 587 adults living in the UK (85 % women; mean age = 32.87 years) completed assessments every two months over five timepoints from May/June 2020 to January/February 2021. Measures included body esteem, disordered eating, and psychological distress. Mixed effect models showed small but significant improvements in body esteem and disordered eating symptoms from May/June 2020 to January/February 2021. These improvements were independent of changes in psychological distress, and did not vary by gender, age or eating disorder history. Whilst poor body image and disordered eating may have been elevated in the early period of the pandemic, this study suggests improvements, rather than worsening, of these outcomes over time. This may reflect adaptation to this changing context.

A Longitudinal and Comparative Content Analysis of Instagram Fitness Posts.

Body dissatisfaction is among the most common mental health challenges experienced by women and has been identified as a risk factor for disordered eating. Research has found that exposure to social media images depicting thin, muscular bodies, often dubbed 'fitspiration', may contribute to body dissatisfaction. Image-centred social media platforms, such as Instagram, have rising popularity among adolescents and young adults. However, little is known about the content of images produced by different fitness-related sources, such as those from fitness brands compared with individual users, and how fitness content on social media is evolving over time. This study sought to determine whether Instagram content varied between female fitness influencers and brands and how this content changed between 2019 and 2021. A longitudinal content analysis was conducted on a sample of 400 Instagram images using a coding scheme developed specifically for this project. The scheme coded images for fit ideal body depiction, fitness focus, objectification, and sexualisation. Chi-square tests indicated that female fitness influencer content was more sexualised and portrayed more of the fit ideal, while fitness brands produced more Instagram content with a fitness focus. There were no significant overall longitudinal changes for any of the four key variables. However, when looking at longitudinal changes by account type, fitness-focused influencer content increased while fitness-focused brand content decreased over time. These findings highlight discernible differences in content produced by different Instagram account types. It points future research towards the consideration of potential moderating factors, such as account type, when exploring the impact of social media images on body image and mental health.

Sensory processing and eating behaviours in autism: A systematic review.

OBJECTIVES: The aim of this study was to assess the relationship between sensory processing and a broad range of eating behaviours across the lifespan. METHODS: Five electronic databases of published and unpublished quantitative studies were systematically searched, evaluated for risk of bias and synthesised according to identified eating outcomes. RESULTS: Across 25 studies, there was consistent evidence of a relationship between sensory processing and a range of eating behaviours. There was early evidence for the particular role of taste/smell sensitivities, as well as hypersensitivities, although future research is needed looking at different sensory patterns and modalities. There was also tentative evidence to suggest this relationship extends across development. DISCUSSION: Study findings are discussed in relation to implications for sensory-based eating and feeding interventions and the development of eating disorders. Methodological and conceptual limitations are discussed and suggestions for future research are made to address these limitations. A broader investigation of multi-sensory issues and clearly defined eating behaviours, including disordered eating in clinically diagnosed samples, will allow for a more comprehensive and robust understanding of the relationship between sensory processing and eating behaviours in autism.

Changes in peer and sibling victimization in early adolescence: longitudinal associations with multiple indices of mental health in a prospective birth cohort study.

Victimization by peers and siblings is associated with poorer mental health outcomes in adolescence. What is less clear is whether mental health outcomes improve if victimization experiences cease (e.g., being victimized in primary school but not secondary school). This study aims to explore how changes in victimization experiences are associated with changes in mental health outcomes in early adolescence. Data are from 13,912 participants in the Millennium Cohort Study (MCS), a nationally representative cohort of individuals born in the UK. Self-reported victimization by peers and siblings, as well as mental health outcomes (depressive symptoms, life satisfaction, self-esteem, and body image), were collected at age 11 and age 14. Victimization at either time point was associated with poorer mental health across the range of outcomes, with effects largest for those who were consistently victimized. Those who reported increasing victimization had greater deterioration in their mental health compared with their peers who were never victimized. Conversely, children whose victimization decreased showed similar mental health development over this period as those who were never victimized. There was a cumulative effect of victimization by peers and siblings, with effect sizes generally larger for experiences with peers. Victimization in adolescence is associated with enduring reductions in mental health. Nonetheless, the promising outcomes associated with reductions in victimization suggest the potential for bullying interventions in schools to limit the deterioration in mental health in victimized groups.

Exploring the association between parental anti-fat attitudes and restrictive feeding practices in a British and Irish sample.

Parental restriction of food intake has been associated with heightened eating disorder psychopathology in some longitudinal research. Yet, relatively little is known about the determinants of restrictive feeding practices. This cross-sectional study explored the association between parents' anti-fat attitudes and their use of restrictive feeding practices in a mixed British (41.10% England, 39.90% Scotland, 4.20% Other) and Irish (14.80%) sample. Parents and caregivers (N = 472; 94.10% female; 70.90% university level education) of children between the ages of 4-8 (48.20% female; 91.10% rated as "normal weight" by their parents) completed self-report questionnaires assessing their anti-fat attitudes (dislike, fear, and blame subscales), use of restrictive feeding practices (for weight control, health purposes, and covert restriction), and how influential their child's body-weight and -shape is for their perception of themselves as parents. Overall, our hypothesis that parental anti-fat attitudes would be significantly associated with restrictive feeding practices was supported. Anti-fat attitudes related to disliking higher body-weight people and blaming parents for their child's weight were significant predictors of all forms of restrictive feeding (all ps < .05). However, anti-fat attitudes related to fearing being a higher body-weight were not significant predictors of restrictive feeding for the purposes of health nor for covert restriction (ps > .05). Additionally, our hypothesis that the associations between anti-fat attitudes and restrictive feeding practices would be stronger for parents for whom their child's body-weight and -shape more strongly influenced how they judged themselves as parents was not supported (the interaction term was not significant in two out of three analyses). Future research is needed to investigate these associations across time and in samples of higher body-weight children.

A network meta-analysis of psychological interventions for schizophrenia and psychosis: Impact on symptoms.

BACKGROUND: Evidence for the effectiveness of psychological interventions for schizophrenia/psychosis is growing, however there is no consensus on the psychological intervention most likely to reduce symptoms. METHODS: A network meta-analysis was conducted to identify all randomised controlled trials (RCTs) of psychological interventions for adults with schizophrenia/psychosis. A systematic review of the literature using MEDLINE, PsycINFO, EMBASE and CENTRAL led to an analysis of 90 RCTs with 8440 randomised participants across 24 psychological intervention, and control groups. Psychological interventions were categorised and rated for treatment fidelity and risk of bias. Data for total symptoms were extracted and network meta-analysis, using a frequentist approach, was undertaken using Stata SE v15 to compare the direct and indirect evidence for the effectiveness of each psychological intervention. FINDINGS: Psychological interventions were more likely to reduce symptoms than control groups, and one intervention, mindfulness-based psychoeducation, was consistently ranked as most likely to reduce total symptoms. Subgroup analyses identified differential effectiveness in different settings and for different subgroups. INTERPRETATION: Mindfulness-based psychoeducation was consistently ranked as most likely to reduce symptoms; however all studies were based in China. More RCTs in a variety of cultural contexts would help to elucidate whether these findings generalise internationally. A number of psychological interventions could potentially be more effective than interventions recommended by NICE guidelines, such as CBT and family therapy, and additional RCTs and meta-analyses are needed to generate more conclusive evidence in this regard.

Mixed methods pilot evaluation of interpersonal psychotherapy for body image for adolescents.

Body dissatisfaction is common in adolescence and associated with poor outcomes. The aim of this mixed method pilot evaluation was to determine acceptability, feasibility and preliminary efficacy of Interpersonal Psychotherapy for Body Image (IPT-BI), a school-based group intervention for young people with high levels of body dissatisfaction. Eighteen participants (11-13 years, 78% female) took part in two IPT-BI groups (n = 10; n = 8). Feasibility was measured by recruitment and attrition rates; acceptability using a treatment satisfaction questionnaire and focus groups; and clinical outcomes at baseline, each session and post intervention. The majority of young people (72%, n = 18/25) who were referred or expressed interest went on to take part. Average session attendance was 100% and 89%. Participants expressed high levels of treatment satisfaction with 94% (n = 16/17) rating IPT-BI as 'quite helpful' or 'very helpful' and 94% (n = 16/17) stating they would recommend it to others. Preliminary exploration of efficacy showed significant improvements in body image and significant reductions in interpersonal difficulties and appearance-based conversations. Young people valued specific IPT-BI skills (role play, communication strategies), alongside generic therapeutic factors (therapeutic alliance, group cohesion). IPT-BI is feasible and acceptable with promising provisional clinical outcomes indicating the need for a fully powered randomised controlled trial.

Exploring changes in body image, eating and exercise during the COVID-19 lockdown: A UK survey.

Early reports suggest that lockdown measures associated with the COVID-19 pandemic (e.g., social distancing) are having adverse consequences for people's mental health, including increases in maladaptive eating habits and body dissatisfaction. Certain groups, such as those with pre-existing mental health difficulties, may be especially at risk. The current study explored perceived changes in eating, exercise, and body image during lockdown within the United Kingdom, using an online survey (n = 264). There were large individual differences in perceived changes in eating, exercise, and body image in this period. Women were more likely than men to report increasing struggles with regulating eating, preoccupation with food and worsening body image. Those with a current/past diagnosis of eating disorders reported significantly greater difficulties in regulating eating, increased preoccupation with food, exercise thoughts and behaviours and concern about appearance, even when compared to those with other mental health and developmental disorders. Ongoing research to explore individual differences in the trajectories of change in eating, exercise and body image as lockdown measures ease will be important for understanding the full psychological impact of this pandemic and improve service and public health planning going forward.

A qualitative exploration of the impact of COVID-19 on individuals with eating disorders in the UK.

COVID-19 may have substantial impact on the mental health at a population level, but also has the potential to significantly affect those with pre-existing mental health difficulties such as eating disorders. This qualitative study explores the impact of COVID-19 and associated public health measures on adults with eating disorders within the UK. We conducted 10 in depth interviews with adults (24-38 years) with a self-reported eating disorder during lockdown. Data were analysed using an inductive thematic analysis approach. We identified core themes related to social restrictions (social isolation, changes in accountability to others, and increased responsibility for self and others), functional restrictions (lack of routine and structure, a need to intentionally plan activity, a desire for secrecy particularly around food shopping) and restrictions in access to mental health services. Overall, the impact of the lockdown was experienced as a catalyst for either increased disordered eating behaviours or for a drive for recovery, depending on individual circumstances going into these restrictions. This study is the first in depth interview approach with adults with mixed eating disorder presentations in the UK during COVID-19. Findings have important implications for post lockdown intervention care and practice.

The psychometric properties of Orthorexia Nervosa assessment scales: A systematic review and reliability generalization.

The main objective of this systematic review was to provide a comprehensive overview of the psychometric properties of all available Orthorexia Nervosa (ON) assessment tools, in order to evaluate their scope of application for research and practice. Ten databases were searched for studies quantitatively assessing ON. The psychometric properties were evaluated according to specified quality criteria, focusing on the reliability, structural validity and construct validity of the scales. A meta-analytic approach was used to summarize eligible Cronbach's alpha coefficients between studies. Sixty-eight unique studies fulfilled the inclusion criteria for this systematic review. Ten discrete ON scales were identified. Half of the included studies exclusively utilized a version of the ORTO-15. The evaluation of all available ON measures raise issues regarding ON's dimensionality and conceptualization. Most of the identified scales require further validation. Based on the reported psychometric properties it is advised to re-evaluate existing tools and to focus on establishing consensus regarding the conceptualization of ON to establish a measure with sound psychometric properties.