Evidence Base - Research into the success rates of emetophobia-free

Exploring The Efficacy of ‘The Thrive Programme’ with
Emetophobic Clients: Results of a Preliminary Survey

Kelly, R.C.* & Allen, C.E.L.

ABSTRACT: This paper presents the results of a preliminary online survey, which explored the efficacy of the Thrive Programme for clients with emetophobia. Results suggest that the Thrive Programme had a significant impact upon the participants’ emetophobia severity, as well as upon their locus of control, self-esteem and social anxiety. Further research is needed to explore whether improvements are maintained at long term follow up.

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Key words: emetophobia, vomit phobia, specific phobia of vomiting, SPOV, The Thrive Programme
*Correspondence to: Robert Kelly (info@thriveprogramme.org)

INTRODUCTION:

Emetophobia, a phobia of vomiting, is a relatively common but under-researched psychological disorder. Vandereycken (2011) explored professionals’ (including psychologists, psychiatrists, nurses and social workers) views of emetophobia. Although 48.6% of respondents had seen cases in their own practice, 29.7% of the 111 participants had never heard of the phobia. A majority (61.3%) of the professionals regarded the disorder as deserving of more attention.

Within the research literature, various terms have been used to refer to a phobia of vomiting, including: fear of vomiting, emetophobia, and specific phobia of vomiting (SPOV). Studies have suggested that the point prevalence of emetophobia or a fear of vomiting is between 0.1% (Becker et al., 2007) and 8.8% (van Hout & Bouman, 2011). Different criteria have been used to assess the fear; these differences may have led to difficulties in making comparisons between studies and resulted in the emergence of varying prevalence rates for emetophobia. Individuals with emetophobia are predominantly female, with studies revealing that 85-97% of their emetophobic participants are women (Lipsitz, Fyer, Paterniti, & Klein, 2001; van Hout & Bouman, 2011; Veale & Lambrou, 2006).

Previous research has suggested that most individuals with emetophobia predominantly fearthemselves vomiting (Lipsitz et al., 2001; van Hout & Bouman, 2011; Veale & Lambrou, 2006). Many have an additional fear of others vomiting because they believe that this would put them atrisk of being sick themselves. Studies have also suggested that a minority of individuals with this phobia only fear others vomiting (Lipsitz et al., 2001; Veale & Lambrou, 2006).

A phobia of vomiting often has a severe impact upon sufferers’ lives. Research studies have indicated that emetophobic individuals show impairments across many domains of their lives (Lipsitz et al., 2001; e.g. van Hout & Bouman, 2011; Veale & Lambrou, 2006). Many engage in a range of safety-seeking and avoidance behaviours in an attempt to prevent themselves from vomiting, including, for example, avoiding particular forms of transport, restricting their food, maintaining very high levels of hygiene, avoiding becoming pregnant and keeping away from people who are ill.

Emetophobia often starts in childhood. Lipsitiz et al (2001) reported that the mean age of onset of the disorder was 9.2 years in their sample. Veale and Lambrou (2006) found a mean age of onset of 9.8 years, with participants suggesting that their symptoms first became a problem at a mean age of 11.6 years. Research has suggested that the condition often has a chronic course, with average durations of the phobia exceeding 20 years at the time of research participation (Lipsitz et al., 2001; Veale & Lambrou, 2006).

Proposed causal and maintaining factors in emetophobia

Research has suggested that many people with emetophobia have experienced an aversive episode of vomiting. Some individuals develop the fear after a gastrointestinal illness or hospitalisation which included nausea or vomiting (Klonoff, Knell, & Janata, 1984; Williams, Field, Riegel, & Paul, 2011). One recent study (Veale, Murphy, Ellison, Kanakam, & Costa, 2013) found that those with  emetophobia rated their autobiographical memories of vomiting as significantly more distressing than the control group, as well as recalling more memories of others being sick. The authors suggested that sufferers could develop their fear through classical conditioning, whereby an experience of vomiting could lead to the phobia, or through vicarious learning, where watching others vomit or acting fearfully in relation to vomit could be sufficient for the development of emetophobia.

Unpleasant experiences of vomiting seem, however, to play only a small role in the development of the phobia. Indeed, since most people experience unpleasant episodes of vomiting at some point during their lifetime but do not develop emetophobia, other factors must be important contributors to this phobia. One study (Klonoff et al., 1984) explored a fear of vomiting in children, which began after a hospitalisation or illness which included nausea or vomiting, suggested that a combination of developmental transitions in the children’s lives, psychological stressors and parental reinforcement of the symptoms helped to maintain their fears.

Sufferers’ cognitions and avoidance behaviours play a substantial role in maintaining their emetophobia (e.g. Boschen, 2007; Veale, 2009; Veale & Lambrou, 2006). Veale (2009, p. 279) has discussed that safety-seeking and avoidance behaviours “have an unintended consequence of increasing the frequency of thoughts about vomiting and symptoms of nausea and will prevent disconfirmation of the threat of vomiting.” Boschen (2007) emphasised that a tendency to somatize anxiety as gastrointestinal distress, catastrophic misappraisal of nausea and other gastrointestinal symptoms, hypervigilance to gastrointestinal cues, beliefs about the unacceptability of vomiting, avoidance behavior, and selective confirmation biases all contribute to emetophobia. Recently, Höller, van Overveld, Jutglar and Trinkaausea (2013) specifically explored nausea in relation to emetophobia and found that the majority of participants reported suffering from nausea at least once a week. They found that emetophobic individuals in a high nausea group demonstrated higher fear levels and a longer duration of fear compared to those in a low nausea g roup. The authors proposed (p.453) that sufferers’ “preoccupation with nausea could lead to a higher probability of experiencing
nausea, especially if nausea is indeed closely associated with stress.”

A link has also been established between emetophobia and disgust propensity (how often people experience disgust) and sensitivity (the extent to which people evaluate disgust-related experiences negatively) (van Overveld, de Jong, Peters, van Hout, & Bouman, 2008). An emetophobic group demonstrated significantly higher levels of both disgust propensity and disgust sensitivity compared to a control group. Additionally, disgust sensitivity was consistently the best predictor of emetophobia complaints. The authors noted that woman generally have higher levels of disgust propensity, which may help to explain the gender bias in emetophobia. Veale (2009, p. 273) has suggested that gender differences in the way in which individuals perceive vomiting may also be seen in the normal population and that “men may be more likely to view vomiting as a joke and even desire to vomit after heavy drinking.”

Davidson, Boyle, & Lauchlan (2008) explored the relationship between emetophobia and locus of control. Their study suggested that emetophobic individuals have a more internal locus of control than participants with other psychological disorders. The authors postulated that an internal locus resulted in a fear of losing control, and that this contributed the development of their emetophobia. The notion that emetophobes have an internal locus of control, however, contradicts the first author’s clinical experience. Although those with emetophobia appear to be scared to lose control and have an over-inflated sense of responsibility in relation to preventing themselves from vomiting, he has found sufferers to generally have a relatively low external locus of control, particularly in relation to emotional and coping domains, whilst also holding a high desire for control. It should be noted that locus of control and desire for control are different concepts (e.g. Burger, 1984; Dembroski, MacDougall, & Musante, 1984; Gebhardt & Brosschot, 2002). Desire for control refers to the amount of control people want, whereas locus of control refers to the amount of control they believe that they have over their lives. Other research has indicated that those with OCD have a high desire for control but a low sense of control and it is possible that this could also be the case for those with emetophobia (e.g. Moulding, Doron, Kyrios, & Nedeljkovic, 2008). Control related beliefs could, therefore, be worth exploring further in relation to emetophobia.

Overlap with other disorders

Researchers have noted that emetophobia shows similarity with a number of other disorders, including obsessive compulsive disorder (OCD), panic disorder, health anxiety and social anxiety (Boschen, 2007; Veale, 2009; Veale & Lambrou, 2006). Where overlapping symptoms are specifically related to the fear of vomiting, comorbid diagnoses are not made. Individuals with emetophobia can, however, also have comorbid diagnoses.

Veale, Hennig and Gledhill (2015) reported repetitive thinking and behaviours in those with a specific fear of vomiting, similar to the phenomenology of OCD. They found a comorbidity with OCD in 12% of cases. Sykes, Boschen and Conlon (2016) found a similar prevalence and reported that an OCD diagnosis was 10.8 times more likely in those with emetophobia compared to the community. As with panic disorder, those with a fear of vomiting may experience recurrent panic attacks. Sykes et al. (2016) found that, in their sample, those with emetophobia were 4.5 times more likely to be diagnosed with panic disorder in a sample than a community sample.

In common with health anxiety, many emetophobes also show significant concerns about their health, worrying about illnesses that could cause vomiting. Some sufferers, also, attribute nausea caused by anxiety to physical problems (Veale, 2009). Like those with social anxiety, many emetophobia sufferers experience social evaluative concerns, worrying that others will appraise them negatively if they vomit (Boschen, 2007). Lipsitz et al (2001) found that 62% of their sample were more anxious about vomiting in public than in private.

Sykes et al. (2016), however, found that comorbid diagnoses were much lower when clinician diagnosed compared to self-report measures. In their sample, diagnoses of social anxiety disorder, posttraumatic stress disorder (PTSD), major depressive disorder, bipolar and body dysmorphic disorder rates were lower than those found in the epidemiological sample.

Treatment of emetophobia

There has been relatively little research into the treatment of emetophobia. Veale and Lambrou (2006, p. 139) have reported that “clinicians generally regard it as challenging to treat because of high drop out or a poor response to treatment.” They additionally found that twenty-nine percent of their sample had received some form of therapy for their fear, which, overall, they rated as largely ineffective.

Veale (2009) has provided a comprehensive cognitive behavioural formulation for a specific phobia of vomiting. There have been a number of case reports of the successful use of cognitive and behavioural techniques (e.g. Hunter & Antony, 2009; Maack, Deacon, & Zhao, 2013; Moran & O’Brien, 2005; O’Connor, 2004; Philips, 1985) and, more recently, several small-scale trials have been conducted. One study explored cognitive behavioural group therapy with 23 participants (Ahlen, Edberg, Di Schiena, & Bergström, 2015). Just under half (48%) of the patients were clinically significantly improved or recovered immediately after treatment, and 67% were improved or recovered at follow-up. The first randomised control trial evaluating CBT for a specific phobia of vomiting took place with 24 participants (Riddle-Walker et al., 2016) and found that, the end of the treatment, CBT was significantly more efficacious than the wait list with a large effect size. Six (50%) of the participants receiving CBT achieved clinically significant change and eight (58.3%) achieved reliable improvement on the Specific Phobia of Vomiting Inventory compared to 2 (16%) participants in the wait list group.

A recent case study explored a transdiagnostic CBT approach (Paulus & Norton, 2015). Transdiagnostic CBT bridges together commonalities in treatment approaches, treating the person as a whole rather than focusing on one specific diagnosis. This approach is postulated to be particularly valuable for more complex presentations, which may be pertinent to emetophobia due to its high comorbidity and overlaps with other disorders. In this case study, transdiagnostic CBT was found it to be effective in reducing scores upon both vomit related and more general anxiety measures. No long-term follow-up was, however, obtained.

The Thrive Programme

Within his practice, the first author has developed The Thrive Programme, a psycho-educational intervention programme. The Thrive Programme aims to provide individuals with an understanding of how their beliefs and ways of thinking contribute to their mental health. Psychoeducation is an essential part of the programme: increasing people’s understanding of themselves is seen to empower and facilitate change.

The programme encompasses exercises and techniques designed to enable people to alter these detrimental cognitions, similar to a CBT approach. The programme also differs significantly from standard CBT treatment protocols, having more in common with a transdiagnostic approach, as it aims to treat people holistically and is not targeted at specific diagnoses. The programme is underpinned by the perspective that the same underlying psychological systems are important to mental health in all cases, and aims to teach people fundamental skills to manage their overall mental health and wellbeing. A core focus is upon building a high sense of control and developing coping skills. Highlighting the importance of this, recent research has found that improvements in perceived control during treatment robustly predicted improvement in all anxiety disorders examined within the study (Gallagher, Naragon-Gainey, & Brown, 2014).

Emetophobia is one of the most common symptoms for which the first author is consulted in his practice. Given the relative paucity of research into the treatment of emetophobia, developing and research effective interventions is of key importance. Follow-up of and feedback from clients suggested that the Thrive Programme is effective at reducing emetophobia symptoms. This study was a small scale preliminary exploration of the effectiveness of the Thrive Programme with emetophobic clients, carried out internally by the Thrive Programme research team.

METHOD:

Participants

Participants included 62 volunteer individuals, who had undertaken the Thrive Programme to address self-reported emetophobia. Respondents included 57 women and 4 men. The mean age was 34 years (range 13 to 63 years). One volunteer was excluded entirely from the study due to large amounts of missing data.

A comparison group of 50 volunteer individuals with other mental health issues (including general anxiety, social anxiety, sexual problems, depression and weight loss) had a mean age of 37 years (range 20 to 72 years) and included 34 women and 16 men. This comparison group was included to provide a tentative reference point for exploring how individuals with emetophobia compared to others seeking help for mental health issues.

Procedure

(i) Intervention Protocol

All participants undertook the Thrive Programme. The programme required individuals to follow a workbook (Kelly, 2010), which they were able to complete alone, or alongside weekly sessions with a Thrive Programme Coach ®, a practitioner who had been trained to provide guidance and support. Through following the workbook, individuals were required to complete regular ‘homework’ to support their learning and change. The programme encompassed modules covering the following:

1. 1. Beliefs and schemas: The ways in which our belief systems and schemas shape our views and interactions with the world was discussed. The metaphor of ‘spectacles’ through which we view the world was used.
   2. Sense of control: The importance of our sense of control to wellbeing and the relevance of a low sense of control and feelings of hopelessness in many mental health issues was detailed. Strategies for developing a sense of control and better coping skills were covered.
   3. Self-esteem: self-esteem was explored and strategies for building healthy self-esteem were covered.
   4. Social pressures: Social relationships, social fears and social anxiety were explored. Strategies for building confidence in social situations were covered.
   5. Language: the importance of the language we use in our self-talk was covered. The benefits of active and positive language were detailed.
   6. Thinking styles: unhelpful ways of thinking (such as dichotomous thinking, catastrophising and ruminating) and their origins were explored. Strategies and homework exercises to
      minimise unhelpful thinking were covered.
   7. Responding to stressors: ways of managing stress and anxiety were explored. Anxiety was conceptualised as occurring when perceived stressors outweigh perceived coping skills as this was discussed in relation to the individual’s life.
   8. Thriving: this programme content was recapped and clients tracked and acknowledged their progress.

The majority (53, 85.48%) of emetophobic participants visited a Thrive Programme Coach ®. The mean number of hour-long sessions undertaken was 7.01 (range 4 to 14). Most of the comparison group (47, 94.00%) also visited a Thrive Programme Coach ®. The mean number of sessions they undertook was 6.94 (range 3 to 24). Nine emetophobic participants had undertaken the Thrive Programme mostly by reading the Thrive Workbook at home, although some of these individuals had additionally seen a Thrive Programme Coach ® for a single support session. Three of the comparison group had undertaken the programme solely by purchasing and reading the workbook.

(ii) Survey Questionnaire

The questionnaire was self-administered online following completion of the programme. The online form explained the purpose of the research, detailed that the survey was anonymous, and asked participants for their consent.

The questionnaire asked participants to rate the severity of their symptoms before and after completing the Thrive Programme on a four point scale which included: little to no; modest; significant; and severe impact. Participants with emetophobia were additionally asked to complete a newly developed measure to assess their emetophobia severity (the Emetophobia Severity Scale, ESS) (Appendix, which had been developed using other existing measures (Boschen, Veale, Ellison, & Reddell, 2013; Veale et al., 2012). Higher scores represented greater severity and impairment (possible range 0 to 30). Individuals were asked to complete this measure both in relation to their current status and retrospectively prior to starting the programme.

Finally, all participants were asked to fill in their scores for measures of locus of control, self-esteem and social anxiety, before and after completing the programme (Kelly, 2010). All respondents had completed these three scales within their workbook, as part of undertaking the programme, in order to gain self-insights and track their progress. These measures were not validated scales but, so as to decrease participant burden, they were the measures used within this preliminary research survey.

RESULTS:

Clinical Features of Emetophobia

The emetophobic participants reported that their phobia had started at a mean age of 11 years (range 5 to 22 years). On average these clients had been suffering from their fear for 23 years (range 4 to 55 years). Almost all (61, 98.39%) emetophobic respondents rated their phobia as having a severe impact upon their lives (on a four point scale which included: little to no; modest; significant; severe), with the remaining participant rating the phobia as significant. This was in contrast to the comparison group, of whom the majority (35, 70.00%) rated their symptoms as having a significant impact. Twelve (24.00%) of the comparison group rated their symptoms as severe, two (4.00%) rated them as having a modest impact and one (2.00%) as having little or no impact on their lives. The emetophobic participants also completed a measure of emetophobia severity (ESS), where higher scores represented greater severity and impairment (possible range 0 to 30). Participants scored an average of 25.11 (range 18 to 30).

Emetophobic participants’ initial locus of control, social anxiety and self-esteem scores were compared to those of the comparison group, prior to undertaking the Thrive Programme, using independent samples t-tests. The emetophobic and comparison groups contained unequal sample sizes, with substantially more participants in the emetophobic group, and the assumption of homogeneity of variance was also violated for all measures. T-tests are not robust in the face of violation of homogeneity of variance and unequal sample sizes (Field, 2009). As a consequence, the sample sizes were balanced, by selecting a random sample from the emetophobic participants, equal in size to that of the comparison group. It should, however, be noted that this approach does lose statistical power, due to the reduction in data. Where there was missing data, participants were excluded from analyses.

For locus of control, the data did not meet all the assumptions of normality, with kurtosis outside of ±1 and the Shapiro-Wilk test reaching significance for the emetophobic group. The equivalent non-parametric test was, therefore, also conducted. This gave comparable findings, so the results of the parametric test are reported. An independent samples t-test assuming unequal variances found a significant difference in the initial locus of control scores of the emetophobic participants (M = 24.59, SE = 0.34) compared to the comparison group (M = 21.37, SE = 0.53), t(82.02) = 5.16, p <0.001, r = 0.49, with the emetophobes scoring more externally. This represented a medium effect.

The initial social anxiety and self-esteem scores of the emetophobic and comparison group were also compared in the same way. Again, both parametric and non-parametric tests were conducted, due to some violations of assumptions of normality. As both gave comparable findings, the results of the t-tests are reported here. There was also a significant difference in the initial social anxiety scores of the emetophobic participants (M = 16.25, SE = 0.30) compared to comparison group (M = 12.60, SE = 0.59), with the emetophobes displaying higher levels of social anxiety, t(68.98) = 5.50, p < 0.001, r = 0.55. This represented a large effect.

The Thrive Programme Intervention Response

The treatment response of the emetophobic participants was also explored. All participants had fully completed the Thrive Programme. After finishing the programme, the majority (55, 88.71%) of the emetophobic participants rated their symptoms as having little to no impact on their lives. The remaining seven (11.29%) rated them as having a modest impact.

A Wilcoxon signed-rank test (the non-parametric version of a dependent samples t-test, due to violation of parametric assumptions) found a significant decrease in the emetophobic participants’ Emetophobia Severity Scale (ESS) scores after completing the programme (Mdn = 4.5, Mean = 4.59, SD = 2.33) compared to their initial scores (Mdn = 25, Mean = 25.18, SD = 2.77), z = -6.52, p < 0.001, r = -0.87. A higher score represented greater severity of emetophobic symptoms, indicating that participants’ severity substantially decreased after completing the programme.

The initial and final locus of control, self-esteem and social anxiety scores of the emetophobic participants were also compared using Wilcoxon signed-rank tests. A significant decrease in the participants’ locus of control scores post the Thrive Programme (Mdn = 4, Mean = 5.27, SD = 3.44) compared to their initial scores (Mdn = 25, Mean = 24.53, SD = 2.54) was found, z = -6.86, p < 0.001, r = -0.87. A higher score represented a more external locus of control, indicating that participants developed a more internal locus of control after undertaking the programme. A significant decrease in the participants’ social anxiety scores (where a higher score represented greater social anxiety) was found post the Thrive Programme (Mdn = 3, Mean = 3.62, SD = 2.12) compared to their initial scores (Mdn = 16, Mean = 16.51, SD = 2.01) was found, z = -6.82, p < 0.001, r = -0.87. Finally, a significant decrease in the participants’ self-esteem scores (where a higher score represented lower self-esteem) post the Thrive Programme (Mdn = 3, Mean = 3.29, SD = 1.76) compared to their initial scores (Mdn = 16, Mean = 15.49, SD = 2.36) was found, z = -6.69, p < 0.001, r = -0.87, suggesting that the participants’ self-esteem increased.

DISCUSSION AND CONCLUSIONS:

The findings of this study in many ways supported prior research into emetophobia. The emetophobic participants reported that their phobia had started at a mean age of 11 years, which agreed with other findings that emetophobia tends to start in childhood (Lipsitz et al., 2001; Veale & Lambrou, 2006). In this study, participants had been suffering from their fear for a mean duration of 23 years, in line with research suggesting that the condition often has a chronic course (Lipsitz et al., 2001; Veale & Lambrou, 2006).

Almost all the emetophobic participants rated their phobia as having a severe impact upon their lives prior to intervention, which is consistent with the findings of other studies. Lipsitz et al (2001, p. 150), for example, found that, “Over 90% of respondents said they experienced distress from emetophobia symptoms 52 weeks a year. Over 70% said they were distressed 6 to 7 days a week.”

The findings in relation to locus of control contrast with those of Davidson, Boyle, & Lauchlan (2008), who found that emetophobes have a more internal locus of control than participants with other psychological disorders. Here the emetophobic participants appeared to have a more external locus of control than a comparison group of participants, a finding that supported the first author’s clinical experience. There could be a number of reasons for these differing findings. Firstly, differences in the measures used to assess locus of control within the two studies could account for the differing findings. Although some people with a fear of vomiting may have an internal locus of control in relation to many domains in their lives, they may nonetheless be external in emotion and cognition related domains. These areas may not have been explicitly probed in Davidson, Boyle and Lauchlan’s study, whereas these areas were included within the locus of control measure within the present study.

There were, however, a number of limitations to this study, which may have affected the findings and could account for the discrepancy. Although the locus of control scale used here was based upon other existing scales, it has not been psychometrically validated. In both the present study and that conducted by Davidson, Boyle, & Lauchlan, there were disparities between the emetophobia and comparison groups, which could also account for differences. Here, there were gender and age differences between the two groups. Matching the groups on demographic variables in future research could minimise this issue. Additionally, the comparison group within this study was comprised of individuals with a diverse range of disorders, which may have influenced findings. Control related beliefs are likely to be worth exploring further in relation to emetophobia.

Findings within this study also indicated that the emetophobic participants had high initial levels of social anxiety, indeed higher than the comparison group, some of whom had consulted specifically for social anxiety. This might indicate that social anxiety plays a role in emetophobia or is increased by having a fear of vomiting. Additionally, there was a significant difference found in levels of self-esteem between the emetophobia and the comparison groups, with the emetophobic group demonstrating lower self-esteem than the comparison group. Further research is needed to explore these findings, since, although the scales used in this study were adapted from other existing scales, they have not been psychometrically validated. Again, group differences may also have impacted upon these findings.

The results of this survey suggested that the Thrive Programme may be an effective treatment for emetophobia, as all participants with a fear of vomiting reported improvements in their condition. Significant improvements were also seen on the emetophobia severity scale (ESS), with emetophobic individuals scoring substantially lower on the ESS after completing the Thrive Programme compared to their initial scores. One strength of this study is that it involved a larger sample than other research, suggesting that widespread successful treatment is possible. These initial results support the notion that interventions that challenge unhelpful beliefs and thinking styles can be successful in substantially improving symptoms of emetophobia.

It should be noted that the emetophobia symptom severity scale needs further research in order explore reliability and validity. Improvements in the ESS scores in this study do, however, agree with the participants’ reported improvements in the extent to which their fear impacted upon their lives, supporting validity. It should be noted that participants were self-diagnosed with emetophobia and there was no independent verification of the diagnosis, which may have impacted upon the findings. Future research is also needed to explore the clinical significance of any symptom improvements. Clinical significance involves both the patient moving from a clinical population to a non-clinical population and the change being statistically significant (Jacobson & Truax, 1991). Follow up of the emetophobic participants was not conducted, so it is not known whether gains were maintained long-term. Feedback from The Thrive Programme clients has indicated that improvements are usually maintained, however, future research is needed to formally assess this.

Clinical presentation, demographic and outcome differences between those who had sessions with a Thrive Programme Coach ® and those who completed the workbook alone were not explored due to relatively small sample sizes. This would be useful to examine in future research, as a self-directed guided workbook could be a cost-effective and accessible intervention.

This preliminary study involved participants completing the online survey questionnaire at the end of the programme completion. Participants were asked to retrospectively rate their emetophobia symptoms prior to beginning the programme, which could have led to recall errors. Future research could address this issue by asking participants to complete a survey before, during and after engaging in the intervention. Additionally, future research would benefit from using validated scales. The scales used in this project were chosen for convenience and to reduce participant burden but they were not psychometrically validated.

This study did not include a control group who did not receive treatment. The chronic nature of emetophobia (Lipsitz et al., 2001; Veale & Lambrou, 2006), however, indicates that it is unlikely that many of the participants in this study would have seen substantial improvements in their condition without intervention. The also study took place within a private setting with paying clients. Paying for a session may increase perceived investment and provide motivation to complete the programme. The findings may only be generalisable to other individuals both willing and able to pay for treatment. Additionally, all participants were volunteers, potentially biasing the sample. Although the findings suggest that the Thrive Programme may be a promising intervention, there were significant limitations to the study and more robust research is now called for. Continued research into the efficacy of the Thrive Programme is planned, facilitating evidence based practice and the development of the programme. As mentioned previously, this preliminary research was conducted internally by the Thrive Programme. Future research conducted or overseen by an independent body would also be beneficial, in order to minimise any potential for bias.

Declarations of interest:

Robert Kelly is the founder of The Thrive Programme and stands to gain financially from any success of the programme.

Charlotte Allen has been employed by The Thrive Programme to assist in conducting the above research.

REFERENCES:

Ahlen, J., Edberg, E., Di Schiena, M., & Bergström, J. (2015). Cognitive behavioural group therapy for emetophobia: An open study in a psychiatric setting. Clinical Psychologist, 19(2),
96–104.

Becker, E. S., Rinck, M., Türke, V., Kause, P., Goodwin, R., Neumer, S., & Margraf, J. (2007). Epidemiology of specific phobia subtypes: findings from the Dresden Mental Health Study.
European Psychiatry, 22(2), 69–74.

Boschen, M. J. (2007). Reconceptualizing emetophobia: A cognitive–behavioral formulation and research agenda. Journal of Anxiety Disorders, 21(3), 407–419.

Boschen, M. J., Veale, D., Ellison, N., & Reddell, T. (2013). The emetophobia questionnaire (EmetQ-13): Psychometric validation of a measure of specific phobia of vomiting
(emetophobia). Journal of Anxiety Disorders, 27(7), 670–677.

Burger, J. M. (1984). Desire for control, locus of control, and proneness to depression. Journal of Personality, 52(1), 71–89.

Davidson, A. L., Boyle, C., & Lauchlan, F. (2008). Scared to lose control? General and health locus of control in females with a phobia of vomiting. Journal of Clinical Psychology, 64(1), 30–39.

Dembroski, T. M., MacDougall, J. M., & Musante, L. (1984). Desirability of control versus locus of control: Relationship to paralinguistics in the Type A interview. Health Psychology, 3(1), 15–26.

Field, A. (2009). Discovering Statistics Using SPSS (Third Edition). Sage Publications Ltd.

Gallagher, M. W., Naragon-Gainey, K., & Brown, T. A. (2014). Perceived Control is a Transdiagnostic Predictor of Cognitive-Behavior Therapy Outcome for Anxiety Disorders.
Cognitive Therapy and Research, 38(1), 10–22. https://doi.org/10.1007/s10608-013-9587-3

Gebhardt, W. A., & Brosschot, J. F. (2002). Desirability of control: psychometric properties and relationships with locus of control, personality, coping, and mental and somatic complaints in three Dutch samples. European Journal of Personality, 16(6), 423–438.

Höller, Y., van Overveld, M., Jutglar, H., & Trinka, E. (2013). Nausea in Specific Phobia of Vomiting. Behavioral Sciences, 3(3), 445–458.

Hunter, P. V., & Antony, M. M. (2009). Cognitive-behavioral treatment of emetophobia: The role of interoceptive exposure. Cognitive and Behavioral Practice, 16(1), 84–91.

Jacobson, N. S., & Truax, P. (1991). Clinical significance: a statistical approach to defining meaningful change in psychotherapy research. Journal of Consulting and Clinical Psychology,
59(1), 12.

Kelly, R. (2010). Thrive. Rob Kelly Publishing.

Klonoff, E. A., Knell, S. M., & Janata, J. W. (1984). Fear of nausea and vomiting: the interaction among psychosocial stressors, development transitions, and adventitious reinforcement.
Journal of Clinical Child & Adolescent Psychology, 13(3), 263–267.

Lipsitz, J. D., Fyer, A. J., Paterniti, A., & Klein, D. F. (2001). Emetophobia: Preliminary results of an Internet survey. Depression and Anxiety, 14(2), 149–152.

Maack, D. J., Deacon, B. J., & Zhao, M. (2013). Exposure therapy for emetophobia: A case study with three-year follow-up. Journal of Anxiety Disorders, 27(5), 527–534.
https://doi.org/10.1016/j.janxdis.2013.07.001

Moran, D. J., & O’Brien, R. M. (2005). Competence Imagery: A Case Study Treating Emetophobia. Psychological Reports, 96(3), 635–636.

Moulding, R., Doron, G., Kyrios, M., & Nedeljkovic, M. (2008). Desire for control, sense of control and obsessive-compulsive checking: an extension to clinical samples. Journal of
Anxiety Disorders, 22(8), 1472–1479. https://doi.org/10.1016/j.janxdis.2008.03.001

O’Connor, J. J. (2004). Why can’t I get hives: brief strategic therapy with an obsessional child. Family Process, 22(2), 201–209.

Paulus, D., & Norton, P. (2015). Purging Anxiety: A Case Study of Transdignostic CBT for a Complex Fear of Vomiting (Emetophobia). Cognitive and Behavioral Practice.
https://doi.org/10.1016/j.cbpra.2015.08.003

Philips, H. C. (1985). Return of fear in the treatment of a fear of vomiting. Behaviour Research and Therapy, 23(1), 45–52.

Riddle-Walker, L., Veale, D., Chapman, C., Ogle, F., Rosko, D., Najmi, S., … Hicks, T. (2016). Cognitive behaviour therapy for specific phobia of vomiting (Emetophobia): A pilot
randomized controlled trial. Journal of Anxiety Disorders, 43, 14–22.

Sykes, M., Boschen, M. J., & Conlon, E. G. (2016). Comorbidity in Emetophobia (Specific Phobia of Vomiting). Clinical Psychology & Psychotherapy, 23(4), 363–367.
https://doi.org/10.1002/cpp.1964

van Hout, W. J., & Bouman, T. K. (2011). Clinical Features, Prevalence and Psychiatric Complaints in Subjects with Fear of Vomiting. Clinical Psychology & Psychotherapy.
van Overveld, M., de Jong, P. J., Peters, M. L., van Hout, W. J., & Bouman, T. K. (2008). An internet-based study on the relation between disgust sensitivity and emetophobia. Journal of
Anxiety Disorders, 22(3), 524–531.

Vandereycken, W. (2011). Media hype, diagnostic fad or genuine disorder? Professionals’ opinions about night eating syndrome, orthorexia, muscle dysmorphia, and emetophobia. Eating Disorders, 19(2), 145–155.

Veale, D. (2009). Cognitive behaviour therapy for a specific phobia of vomiting. The Cognitive Behaviour Therapist, 2(04), 272–288.

Veale, D., Ellison, N., Boschen, M. J., Costa, A., Whelan, C., Muccio, F., & Henry, K. (2012). Development of an Inventory to Measure Specific Phobia of Vomiting (Emetophobia).
Cognitive Therapy and Research, 1–10.

Veale, D., Hennig, C., & Gledhill, L. (2015). Is a specific phobia of vomiting part of the obsessive compulsive and related disorders? Journal of Obsessive-Compulsive and Related Disorders, 7, 1–6. https://doi.org/10.1016/j.jocrd.2015.08.002

Veale, D., & Lambrou, C. (2006). The psychopathology of vomit phobia. Behavioural and Cognitive Psychotherapy, 34(2), 139.

Veale, D., Murphy, P., Ellison, N., Kanakam, N., & Costa, A. (2013). Autobiographical memories of vomiting in people with a specific phobia of vomiting (emetophobia). Journal of Behavior Therapy and Experimental Psychiatry, 44(1), 14–20.

Williams, K. E., Field, D. G., Riegel, K., & Paul, C. (2011). Brief, Intensive Behavioral Treatment of Food Refusal Secondary to Emetophobia. Clinical Case Studies, 10(4), 304–311.

APPENDIX

Emetophobia Symptom Severity Scale

Anxiety and fearful cognitions

1. I feel very anxious at thought of being sick
2. I often experience physical symptoms (such as nausea, racing heart rate, sweating) at the thought or mention of vomiting
3. I could not cope with being sick
4. I have recently experienced emetophobia related panic attacks
5. I am preoccupied by thoughts of being sick
6. I worry that I will be really ill if I am sick
7. I worry about other people being sick
8. I worry that if I am sick I will die
9. I feel anxious whenever I hear or see the words ‘sick’ or ‘vomit’
10. I worry that I will completely lose control if I vomit

Avoidance and safety-seeking

1. I tend to avoid eating out at restaurants or other people’s houses
2. I avoid taking medication that could cause sickness
3. I have an emergency plan in case of sickness
4. I tend not to go to pubs and clubs for fear of drunk people throwing up
5. I tend not to travel by one or more of: car, boat, train, bus or plane, for fear of vomiting or catching a vomiting bug
6. I maintain very high standards of personal and household hygiene
7. I avoid drinking alcohol or eating specific foods for fear of sickness
8. I avoid going near people that could be unwell
9. I take ‘stomach settlers’, such as drinking mint tea
10. When preparing food I like to double check the sell by date and make sure everything is thoroughly cooked

Social impact

1. I haven’t told other people about my emetophobia
2. Vomiting in front of others worries me more than vomiting in private
3. I think that others would be disgusted if I were to throw up in public
4. I worry about what my friends or family might think of me for having emetophobia
5. I fear that other people might not want to know me if I were to throw up in front of them
6. Whenever I feel anxious, I try to hide it from others
7. I worry that my friends and family might talk about my emetophobia behind my back
8. I worry that being sick would make me look disgusting
9. I fear getting into relationships, due to potentially having to reveal or explain my emetophobia to my new partner
10. I worry that other people might be annoyed if I were to throw up in front of them

The measure was scored using a simple dichotomous rating scale: agree (1) or disagree (0).