The present study protocol is reported according to the SPIRIT checklist (Chan et al., 2013). The study protocol and trial has been approved by a Human Research Ethics Review Board (HREC #X23-8405) and has been registered with the Australia New Zealand Clinical Trials Registry (ANZCTR Registration Number: ACTRN12623000695606p, registered 29 June 2023).
Trial Design and Setting
This study is a 2 (Treatment) x 3 (Time) non-randomised, controlled trial to evaluate the effectiveness of the Body Project as an ED prevention program in a sample of young people presenting for care at a headspace centre. It will compare study outcomes between two treatment groups, the Body Project treatment group versus the Treatment-as-usual control group. Data will be collected at three time points; T1 (Pre), T2 (Post), and T3 (one month follow-up).
All study procedures, including recruitment, treatment, and data collection, will be conducted at headspace Camperdown. headspace Camperdown is a large, metropolitan multidisciplinary youth mental health service with a clinical team including psychologists, GPs, a psychiatry registrar, social workers and exercise physiologists. This service is located within the Brain and Mind Centre at the University of Sydney. headspace Camperdown provides approximately 6000 occasions of service to an average 1200 young people per year, half of which are new patients to the centre (headspace National, 2021). The average age of the young people who attend headspace Camperdown for care is 19.3 years (65.9% female) with 3.5% identifying as Aboriginal or Torres Strait Islander, 24.5% as culturally or linguistically diverse (CALD) and 37.8% as LGBTQIA+ (lesbian, gay, bisexual, transgender, intersex, queer, asexual and other sexually or gender diverse). A high proportion of young people present as either being sad or depressed (39.9%), or anxious (29.5%), to account for 69.4% of total presentations and comparable with national averages (headspace National, 2021).
Recruitment will include a minimum sample of 82 individuals aged 12-25 years. Treatment-as-usual will be utilised as a control condition due to the use of a study setting where individuals are already treatment seeking and maintains other benefits such as controlling for many non-specific therapy factors, and ethical advantages due to not withholding or delaying treatment or care (Kazdin, 2015). Due to external restraints on recruitment and delivery of the program, the study will not be randomised or blinded. All consenting participants will be invited to attend the treatment group and participants will voluntarily elect themselves to be a part of either study condition. See Figure 1 for a flowchart of the study design.
Participants
Participants will be young people aged 12 – 25 years presenting at headspace Camperdown, who have the ability and willingness to provide informed consent, participate and comply with the study. No restrictions will be imposed by gender or other demographic characteristics other than the age range eligibility. No additional exclusion criteria will be applied to consenting individuals beyond those already utilised at headspace Camperdown. These pre-existing exclusion criteria include individuals with a disease or psychological illness that would interfere with their ability to understand the requirements of the study and treatment or interfere with the evaluation of the patient’s safety and of the study outcome.
An a-priori power analysis was run using G*power (Faul et al., 2007). In order to adjust multiple comparisons in the testing procedure, an alpha of 0.05 was adjusted to 0.017 in accordance with the Bonferroni method. An a-priori power of 0.95 was utilised as per the recommended minimum power for planned frequentist analyses, as well as a Cohen’s f effect size of 0.2. Using these estimates, a total sample size of 82 participants was required (41 per group). Thus, for our study to achieve the minimum statistical power using these estimates and to manage for potential participant dropout, we aim to recruit 60 participants (ideally aiming for six groups of 10 participants) for the Body Project treatment group, and a matched 60 participants for the treatment-as-usual control group. This calculation is additionally supported by previous ED trial protocols (Barakat et al., 2021), who obtained similar estimates.
Materials
Body Appreciation Scale (BAS-2)
The BAS-2 (Tylka & Wood-Barcalow, 2015) is a 10-item self-report questionnaire, and is considered a measure of positive body image, examining individuals’ acceptance of, and favourable opinions towards and respect for their body (e.g., ‘I feel love for my body’). Participants are asked to rate whether the item is true of them on a scale of 1 (Never) to 5 (Always), where higher scores indicate higher body appreciation. It had demonstrated good psychometric properties cross-culturally (Razmus et al., 2020).
Depression, Anxiety, Stress Scale (DASS-21)
The DASS-21 is a 21-item self-report questionnaire that examines three related negative emotional states; depression (e.g., ‘I felt that life was meaningless’), anxiety (e.g., ‘I felt I was close to panic’) and stress (e.g., ‘I found it hard to wind down’; (Lovibond & Lovibond, 1995). Participants are asked to rate items according to how much each statement applied to them over the past week on a scale of 0 (Did not apply to me at all) to 3 (Applied to me very much or most of the time), where higher scores indicate higher depression, anxiety and stress. It has demonstrated good psychometric properties across cultures (Zanon et al., 2020).
Eating Disorder Examination Questionnaire Short (EDE-QS)
The EDE-QS is a brief, 12-item version of the more commonly used 28-item EDEQ (Gideon et al., 2016), that assesses ED symptomatology and severity in the seven days prior to assessment (e.g., ‘…Have you had a strong desire to lose weight?’). Ten items are rated on a 4-point scale (0 days [0] to 6-7 days [3]), and two items on a 4-point scale (Not at all [0] to Markedly [3]), where a higher global score reflects greater frequency and severity of symptoms. The short form was utilised to reduce participant burden. The EDE-QS has been seen to be psychometrically and conceptually sound (Gideon et al., 2016).
Ideal Body Stereotype Scale Revised (IBSS-R)
The IBSS-R is a 6-item scale that was originally designed to measure internalization of societally relevant stereotypical female body ideals (Stice & Bearman, 2001). Items are rated on a 5-point scale from 1 (Strongly disagree) to 5 (Strongly agree), where a higher overall score indicates greater endorsement of ideal-body stereotypes. It has demonstrated good internal consistency and test-retest reliability (Stice & Bearman, 2001; Stice & Whitenton, 2002). For the purposes of this study, the scale and its items were adjusted to reflect more contemporary, relevant and gender inclusive ideal-body stereotypes (e.g., ‘People who are “in shape” [fit and strong] are more attractive’).
Inside Out Screener
The Inside Out Screener is a 6-item novel screening tool utilised for early detection for high risk and early stage eating disorders, developed for both self-referral and use in clinical settings (Bryant et al., 2021). One item (‘How is your relationship with food?) is rated on a 5-point scale from 1 (Worry and stress free) to 5 (Full of worry and stress), and the remaining five items (e.g., ‘Does your weight, body or shape make you feel bad about yourself?’) rated on a 5-point scale from 1 (Never) to 5 (All the time). A higher overall score indicates a higher degree of risk. It has shown excellent preliminary evidence for its psychometric properties (Bryant et al., 2021).
Kessler Psychological Distress Scale (K10)
The K10 is a 10-item scale utilised for measuring general psychological distress (Kessler et al., 2002). Items (e.g., ‘In the past 4 weeks, about how often did you feel tired out for no good reason?’) are rated on a scale 5-point scale from 1 (None of the time) to 5 (All of the time), where a higher score indicates higher distress. It has demonstrated good clinical utility, reliability and validity (Batterham et al., 2017).
Perceived Sociocultural Pressure Scale (PSPS)
The PSPS is a 10-item scale used for assessing the perceived pressure to be thin individuals have experienced from individuals from friends, family, and the media (Stice & Bearman, 2001). Items (e.g., ‘I’ve felt a strong message from the media to have a thin body’) are rated on a 5-point scale from 1 (None) to 5 (A lot), with higher scores indicating higher perceived sociocultural pressure. It has demonstrated good internal consistency and test-retest reliability (Stice & Bearman, 2001; Stice & Whitenton, 2002).
Procedure
Participants will be recruited via flyers distributed throughout the trial setting (headspace Camperdown). These will invite individuals to participate in the four week, four-session Body Project program (1.5 hours per session), or to participate by completing questionnaires at the required time points if they participate in the Treatment-as-usual control group. Interested participants will be presented with a participant information statement and consent form to provide informed consent to participate in the study. As part of enrolment, consenting participants will self-allocate to a treatment condition. At this time, participants will receive a unique enrolment number which will be utilised on all study materials and questionnaires. Participants under the age of 18 years of age will also require written parental consent to be provided to finalise enrolment. After informed consent has been provided, participants will complete the T1 [pre-treatment] questionnaire. Questionnaire data will be collected via online self-report using Qualtrics Survey Software. This test battery includes collecting demographic information and all outcome measures outlined in the materials section. Demographic information collected includes age, gender identity, ethnicity, and about current (if any) mental health diagnosis(es). Participants are also asked they have experienced an eating disorder either currently or in the past but have not spoken to a health professional about it in order to obtain a diagnosis.
Intervention will commence after enrolment and allocation procedures have been finalised. Detailed information about the intervention and control conditions have been outlined in the subsequent intervention section. Participants will be closely monitored and assessed for safety and adverse events throughout the entire study period. After the fourth visit to headspace Camperdown to close intervention period, participants will complete the T2 (post-treatment) questionnaire (identical to T1 but without demographic information). One month after the T2 questionnaire has been completed, all participants will be asked to complete the T3 (one-month follow-up) questionnaire. After the close of the study period and data collection is complete, data analysis will be carried out by the chief and co-investigators. Table 1 displays the schedule of enrolment, interventions and assessment in accordance with SPIRIT guidelines.
Intervention
Body Project Treatment
The Body Project treatment program is a cognitive dissonance-based body acceptance intervention (Stice et al., 2012). It is a manualised intervention that consists of four group sessions and was originally designed to help adolescent girls and young women resist sociocultural pressures to conform to the thin beauty-ideal and reduce their pursuit of thinness through written, verbal and behavioural exercises. For our treatment groups, the program will be comprised of four group-based 1.5 hour sessions, running over four consecutive weeks. It contains a variety of key principles and tasks summarised in Table 2. For the purposes of utilising this treatment in an inclusive group of gender diverse individuals, some of the content of sessions were adapted to include and reflect other relevant body ideals (e.g., thin ideal, curvy ideal, fit ideal, muscular ideal). A clinical psychology trainee will lead group-sessions based on the treatment manual.
Treatment-as-usual Control
Participants in the control group will continue to attend headspace Camperdown sessions with their usual clinician/s over the four consecutive week period.
Data Analysis Strategy
Statistical analyses will be carried out using IBM Statistical Package for Social Sciences (SPSS) Statistics (version 26.0) predictive analytics software. Preliminary and descriptive analyses will be conducted to examine general sample characteristics and other variable information. This includes analyses such as examining distribution of data to assess for violations of normality assumptions for all variables, floor and ceiling effects, examining the internal consistency of measures using McDonald’s Omega (Ω), and the relationships between variables using Kendall’s Tau correlations.
To investigate the treatment outcomes and test research hypotheses, F-tests (two-way analysis of variance [ANOVA]) will be conducted to investigate differences in repeated measures within groups (between T1, T2, and T3), and between group differences (between groups effects at T2 [post-treatment] and T3 [one-month follow-up]), and finally to examine the interaction between conditions (time and treatment). Additionally, baseline differences between groups for outcome measures will be examined pre-treatment (T1), and may be used as a covariate. These differences will be examined for all outcome measures (measures of body image, ED symptomatology and general psychological distress). An alpha of 0.05 for testing statistical significance may be adjusted in accordance with the Bonferroni method to allow for multiple comparisons.
Several additional analyses will be considered if they contribute to a more nuanced understanding of study outcomes and assist in the overall interpretation of findings. This includes examining the impact of demographic variables on outcomes using t-tests and chi-square tests, and subsequently utilising these variables as covariates or moderators. Due to the use of ‘forced response’ items in the online test battery, we do not anticipate any missed data.
Ethical Considerations, Data and Risk Management
Informed consent will be obtained by providing participants with a Participant Information Statement and obtaining written informed consent. Parents with children under the age of 18 will also receive a Participant Information Statement and will provide informed consent. Under the TGA CTN Scheme, all data from intervention studies conducted will be kept indefinitely. However, all information will be treated confidentially. All data will be de-identified by the researchers, and only the approved researchers will have access to the de-identified data. All recruitment, data collection and intervention will be supervised by senior clinical psychologists. If participants wish to withdraw from the study once it has started, they can do so at any time without having to give a reason, by contacting the chief-investigator. Data will be stored on a secured server and managed by the approved study investigators.
In the case of an unexpected medical emergency or workplace accident/injury, the WHS policy of headspace Camperdown and UTS will be followed regarding the reporting of incidents. A distress protocol has been created in order support any distressed participants, both during and after the intervention. As the study and intervention are occurring within the participants treatment centre (headspace Camperdown), their treating clinicians and senior clinical staff will be on site to assist with distress. Any instances of negative or adverse outcomes will also be included in trial reports.