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Scared to Lose Control? General and Health Locus of
Control in Females With a Phobia of Vomiting
m
Angela L. Davidson
University of Newcastle Upon Tyne Medical School
m
Christopher Boyle
Lanarkshire Psychological Services and the University of
Dundee
m
Fraser Lauchlan
South Lanarkshire Psychological Services and the University
of Strathclyde
The term emetophobia (i.e., a fear of vomiting) exists as rather an elusive
predicament, often eluding conventional treatment. The present study
involved 149 participants, consisting of 51 emetophobics, 48 phobic
controls (i.e. those who suffered from a different phobia), and 50
nonphobic controls. Participants were administered the Rotter (1966)
Locus of Control Scale and the Health Locus of Control Scale by B.S.
Wallston, Wallston, Kaplan, and Maides (1976). Significant differences
were found among the three groups; specifically, that emetophobics had
a significantly higher internal Locus of Control Scale score with regard to
both general and health-related issues than did the two control groups. It
is suggested that vomiting phobics may have a fear of losing control, and
that their vomiting phobia is reflective of this alternative, underlying
problem. More research is required to explore the association between
emetophobia and issues surrounding control; however, the current study
suggests that it may be helpful for therapists to consider this aspect
when treating a patient with vomiting phobia. &2007 Wiley Periodicals,
Inc. J Clin Psychol 64: 30--39, 2008.
Keywords: emetophobia; phobia; vomiting; control; perfectionism;
emetophobic
Correspondence concerning this article should be addressed to: Christopher Boyle, School of Education,
Social Work & Community Education, University of Dundee, Gardyne Road, Broughty Ferry, Dundee,
DD5 1NY Scotland; e-mail: c.y.boyle@dundee.ac.uk
JOURNAL OF CLINICAL PSYCHOLOGY, Vol. 6 4(1 ), 3 0--39 ( 20 08) &2007 Wiley Periodicals, Inc.
Published online in Wiley InterScience (www.interscience.wiley.com). DO I : 10. 1 0 02/ j c lp. 2 0 431
Introduction
Broadly defined, the term phobia describes a common anxiety disorder characterized
by a persistent fear reaction that is acutely out of proportion to the reality of the
danger. Frequently, the phobia is focused on some specific stimulus or event, and in
some severe cases, it can interfere with the person’s entire life (Rosenhan & Seligman,
1995). Almost anything can act as the subject of a phobia, characterized usually as
either a specific or ‘‘monosymptomatic’’ phobia referring, for example, to heights or
cats; a social phobia referring, for example, to public speaking or restaurant dining;
or agoraphobia referring, for example, to public places or crowds.
The term emetophobia relates to the fear of vomiting, and although largely
unheard of outside the medical nomenclature, its prevalence affects many individuals
worldwide. Consequences on everyday life can vary from minimal to extreme, and
despite the motivation of the person to seek treatment; success stories of those
effectively cured are uncommon and sporadic in the literature (Bouman & van Hout,
2006; Moran, 2005). Emetophobia is a chronic disorder of early onset, relaying
symptoms that are highly persistent and intrusive in nature, which are distressing on
a daily basis (Lipsitz, Fyer, Paterniti & Klein, 2001). There is significant overlap in
the cognitive processes and behaviors with those of panic disorder, such as selective
attention and vigilance; in the case of emetophobia, for nausea and vomiting. In
addition, there also is a significant overlap in the phenomenology with that of
obsessive compulsive disorder, such as fear of contamination (Veale & Lambrou,
2006). Such characteristics of fear, triggered by both internal and external stimuli,
comprising, for example, the sight of another person vomiting, or nausea, tend to
affect individuals with regard to their social, home-marital, and occupational
functioning. The condition also can significantly restrict leisure activities, which may
impact on personal well-being. Almost half of all female emetophobics avoid or
delay becoming pregnant, signifying a serious impact upon their life pattern (Lipsitz
et al., 2001).
Systematic desensitization presents patients with increasing intensities of their
feared object or situation which, when accompanied by relaxation, usually leads to
extinction of the fear response. There are various practical and ethical problems
associated with exposure to vomiting as a method of treatment in emetophobia
(Veale & Lambrou, 2006), as most would regard inducing emesis as harm,
contravening the basic principle of doing no harm. In addition, anecdotal evidence
from an Internet support group for emetophobics, which has been established and
operating for several years, reported no successful instances of desensitization
therapy for those who feared themselves vomiting despite many members reportedly
having attempted it (Listserv, 2003). Listserv is an area on the Internet that hosts
forum groups, and the Emetophobia Support Group was one such group. To gain
access to the group, a person would be required to e-mail the list owners
(emetophobia@listserv.icors.org) with his or her personal story; if the story was
deemed to be genuine, then they would be able to join the group and participate in
the group discussion. For those emitophobics who also were fearful of coming into
contact with vomit, desensitization was reported to result in marked improvement
for this aspect of their problem, but the fear of vomiting still existed. It would
therefore appear that some factor, innate to the act of vomiting, might have an
important role in the persistence of emetophobia despite appropriate intervention.
Locus of control was a very influential topic within psychology research in the
1970s and 1980s. The Rotter (1966) I-E Locus of Control Scale measures an
31Locus of Control in Vomiting Phobia
Journal of Clinical Psychology DOI 10.1002/jclp
individual’s attribution of control as being either internal (I) or external (E). Those
endorsing a predominantly internal locus of control regard events as being within
their influence whereas those endorsing a predominantly external locus of control
regard events to be mainly outside their jurisdiction. There is significant evidence
that anxiety and depression are associated with an external locus of control (Burger,
1984; Dyal, 1984; Ganellen & Blaney, 1984; Joe, 1971; Molinari & Khann, 1981;
Strickland, 1977), and that patients with major depression, social phobia, mixed
anxiety depressive disorder, and panic disorder also have significantly greater
external Locus of Control Scale scores as compared to a control group (Kennedy,
Lynch & Schwab, 1998). There is a clear gap in the literature regarding emetophobia
and its treatment. To date, no one has examined the relationship between
emetophobia and locus of control. Having studied the anecdotal reports of members
of an online support group for emetophobia (Listserv, 2003), it appears that many
report a fear of losing control, which may underlie their emetophobia.
The present research aimed to investigate an association between emetophobia
and an internal locus of control. Emetophobics may be different from those with
other anxiety and depressive disorders in that emetophobics may have an internal
locus of control. This internal locus of control may serve to maintain their
emetophobia by contributing to a fear of losing control. It was hypothesized that
emetophobics would have an internal locus of control, contrary to other anxiety and
depressive disorders.
Rotter’s (1966) Locus of Control Scale was used to ascertain whether emetophobic
participants endorsed a significantly higher internal Locus of Control score
compared to both phobic and nonphobic controls. In addition, B.S. Wallston et
al. (1976) developed and validated the Health Locus of Control Scale, deeming it an
area-specific measure of expectancies regarding locus of control formed for
prediction of health-related behavior. This latter scale was presumed to be a more
sensitive measure of locus of control in emetophobics. Use of both scales allowed us
to determine whether an internal health locus of control is exclusively or inclusively
implicated in emetophobia (if indeed at all), alongside Rotter’s measurement of a
general locus of control.
Method
Participants
The demographic characteristics of all participants, according to the three groups,
are summarized in Table 1.
Emetophobic participants. Participants were recruited through contact on the
Emetophobia Internet Group. They were requested to volunteer and complete a
questionnaire for a study about emetophobia. All interested members e-mailed the
first author, and a reply was sent which included both the Locus of Control Scale
and the Health Locus of Control Scale in Microsoft Word documents. The scales
were completed and then returned by e-mail. The emetophobic group was comprised
of 51 female participants, with a mean age of 31.56 years (range 515–70).
A majority (i.e., n531) of the participants were American, 14 were British, 3
were Australian, and 3 were Other European. Eleven participants were full-time
students, although of the remaining participants, 30 had completed higher education
and were employed in teaching, management consultancy, translation, or law, and 1
participant was a clinical psychologist. Nineteen participants reported no additional
32 Journal of Clinical Psychology, January 2008
Journal of Clinical Psychology DOI 10.1002/jclp
phobias besides emetophobia; of the remaining 32 participants, half stated that they
had phobias (e.g., fear of germs and fear of hospitals) resulting directly from their
emetophobic symptoms. Ensuing arbitrary phobias ranged from spiders and
enclosed spaces to heights and water; 9 participants listed phobias entailing a loss
of physical control including epileptic fits, fainting, and paralysis. Based on their
responses to the questionnaire, almost half of the emetophobic participants suffered
additional self-reported mental health problems—the most common of which were
generalized anxiety disorder and obsessive compulsive disorder, although many
regarded the latter as a direct result of their emetophobia. Of the remaining self-
reported problems, panic disorder and depression were common, and 4 participants
presented as suffering from anorexia nervosa.
Phobic control participants. The phobic control group yielded 48 female
participants who were obtained by canvassing student halls of residence and
University lecture classes, and asking for volunteers to fill out a questionnaire. This
generated the majority of the control participants’ data, although some were
distributed among a range of workplaces such as included hospitals and companies.
A short explanation was given to the participants, which stated that the results were
to be collected for a study on vomiting phobia. The participants were instructed both
orally and via explanations detailed on the front of the questionnaire booklets to
work through the scales independently, allowing approximately 15 min for
completion, with the results gathered immediately thereafter along with short
debriefing. A minority of control group participants were located via e-mail
following word-of-mouth from other participants, resulting in a willingness to
participate. In these circumstances, an identical questionnaire was e-mailed as a
Microsoft Word document attachment, with responses collected in the equivalent
manner.
The mean age of the participants was 23.44 years (range 517–57). Most
participants were either British or Irish, with the exception of 2 American
participants. Although the majority were students at the University of Dundee, 11
participants held full-time jobs that ranged from administrative assistant to auxiliary
nurse. Their phobias were characterized by a wide range, provided in descending
order of endorsement: heights, spiders, enclosed spaces, mice, snakes, needles, water,
wasps, the dark, vampires, flying, and birds.
Nonphobic control participants. The nonphobic control participants were
recruited the same way as the phobic control group (i.e., following lectures and by
canvassing halls of residences). This yielded 50 female participants, with a mean age
of 20.89 years (range 517–57). All participants were either British or Irish, and 42
Table 1
Demographic Data of the Participants
Emetophobics
(n551)
Phobic controls
(n548)
Nonphobic controls
(n550)
Mean age (years) 31.56 (range 515–70) 23.44 (range 517–57) 20.89 (range 517–57)
Nationality
American 31 (60.8%) 2 (4.2%) 0 (0%)
British/Irish 14 (27.4%) 46 (95.8%) 50 (100%)
Other 6 (11.8%) 0 (0%) 0 (0%)
Full-time students 11 (21.6%) 37 (72.5%) 42 (82.4%)
Full-time employment 40 (78.4%) 11 (27.5%) 8 (17.6%)
33Locus of Control in Vomiting Phobia
Journal of Clinical Psychology DOI 10.1002/jclp
were students at the University of Dundee. The remaining 8 participants held various
full-time jobs ranging from health advisor to accountant.
Measures
The materials utilized in this study consisted primarily of (a) a battery of scales
produced in one questionnaire, and (b) information gathered via the Internet since
the majority of emetophobic participants were contacted and communication was
maintained via e-mail. The following information was included in the questionnaire:
Rotter’s Locus of Control Scale (Rotter, 1966), the Health Locus of Control Scale
(B. S. Wallston et al., 1976), and the final page of the questionnaire requesting each
participant’s general information.
While the majority of phobic and nonphobic control participants were provided
manually with a hard copy of the questionnaire on paper to complete, the majority
of emetophobic participants were provided electronically with the questionnaire via
e-mail. Response occurred by the same means.
Rotter’s Locus of Control Scale (Rotter, 1966). This scale consists of 23 pairs of
statements, one of which contains an external control scenario and the other an
internal control scenario. For each pair, the participant was instructed to choose the
one statement that they feel they more strongly believe to be the case. When analyzing
the results, it is possible to add up either the number of internally endorsed items or
the number of externally endorsed items. As the hypotheses of the present study relate
to an internal locus of control, numbers of internal statements were calculated for each
individual and analyzed, producing a measure of internal locus of control for each
participant. Numerous studies have supported the validity, stability, and accuracy of
this measure vis-a
`-vis its psychometric properties (see Zerega, Tseng & Greever, 1976).
Health Locus of Control Scale (B.S. Wallston et al., 1976). This scale consists of 11
health-related statements such as ‘‘If I take care of myself, I can avoid illness’’ (which is
an example of an internal locus of control item), and participants are asked to rate how
much they agree or disagree on a Likert scale ranging from 1 (strongly disagree)to6
(strongly agree). Five items relate to an internal locus of control, and six to an external
locus of control. This scale is used extensively in health settings, and there is extensive
published literature to suggest that psychometric properties of the scale are sound in
that they are able to measure a person’s health locus of control beliefs (K.A. Wallston,
2005). Again, as the hypotheses relate to an internal locus of control, only the results of
the internally worded items were included in the results of this article.
General information requested from the participants was age, gender, occupation,
list of self-reported phobias, and nationality. In addition, the emetophobics were
invited to include any additional self-reported mental health problems. The general
information questions were required so that a better understanding regarding the
broad characteristics of each of the participant groups be obtained and to ensure no
major discrepancies prevailed that could confound the results.
Procedure
The current study used a between-subjects design in which emetophobic,
phobic control, and nonphobic control groups were compared on internal and
health locus of control.
The support group was found by an Internet search using the Google search
engine; subsequently, the list owners were contacted to gain access to the support
34 Journal of Clinical Psychology, January 2008
Journal of Clinical Psychology DOI 10.1002/jclp
group (More detailed joining instructions are contained earlier in this section.), and
an offer of support for a study concerning vomiting was received from its members.
It was explained to all participants that the study of emetophobia was the focus of
the research project and that a full explanation of the various hypotheses would be
provided after data collection. Prospective participants were requested to provide the
first author with their e-mail addresses, where again—in common with the minority
of control participants—an electronic version of the questionnaire was sent as a
Microsoft Word document e-mail attachment. Participants were instructed to return
the completed document by the same means. Upon collection of all responses, full
debriefing occurred via e-mail. As this study was based at a U.K. university, it was
given approval by that institution’s Ethics Committee.
Although male participants were originally invited to participate in the study, only
3 emetophobic males responded; it therefore was determined that only female
participants should be assessed since unequal ratios between the three groups would
likely confound the results.
Following accumulation of the data from all three groups, means and standard
deviations were calculated on the appropriate scores of both scales, classified by
emetophobic, phobic control, and nonphobic control groups. Analyses of Variance
(ANOVAs) were conducted, fundamentally to determine whether any significant
effects of the independent variables existed. Where this was so, post hoc Scheffe tests
were administered to locate specific significant differences between the individual
pairs of groups tested.
Results
The initial scale administered to participants was Rotter’s Locus of Control (LoC).
Table 2 provides these scores for emetophobics, phobic controls, and nonphobic
controls.
A between-groups, one-way ANOVA was conducted on the internal LoC scores,
with the results also summarized in Table 2. The main effects of group on internal
LoC scores were significant at the po.01 level. Post hoc Scheffe tests revealed that
internal LoC scores were significantly greater for emetophobics, as compared to
phobic controls (Mdifference 54.64, SE 50.86, po.01), and as compared to
nonphobic controls (Mdifference 54.40, SE 50.85, po.01). Internal LoC scores
were found not to differ significantly between phobic and nonphobic controls (M
difference 50.24, SE 50.86, p5n.s.).
Table 2
Means, SDs, and Between-Group Comparisons on the Rotter Locus of
Control Scale and Health Locus of Control Scale
Emetophobics
(n551)
Phobic controls
(n548)
Nonphobic controls
(n550)
Measure M(SD)M(SD)M(SD)
Rotter Locus of
Control
Scores
a
13.10 (4.33) 8.46 (3.86) 8.70 (4.56)
Health Locus of
Control Scores
b
3.01 (0.65) 2.37 (0.61) 2.44 (0.65)
a
Between-groups ANOVA: F518.82, po.01.
b
Between-groups ANOVA: F515.45, po.01.
35Locus of Control in Vomiting Phobia
Journal of Clinical Psychology DOI 10.1002/jclp
The second scale administered was the Health LoC scale. Mean scores provided in
terms of the 6-point scale, along with their corresponding standard deviations, are
provided in Table 2 for emetophobics, phobic controls, and nonphobic controls.
Only the scores relating to internal LoC are reported.
A between-groups, one-way ANOVA was conducted on the Health LoC Scale
scores, with results summarized in Table 2. The main effects of group on the Health
LoC Scale scores were significant at the po.01 level. Scheffe tests revealed that
internal Health LoC Scale scores were significantly greater for emetophobics, as
compared to phobic controls (Mdifference 50.64, SE 50.13, po.01). Health LoC
Scale scores were significantly greater for emetophobics, as compared to nonphobic
controls (Mdifference 50.57, SE 50.13, po.01). Health LoC Scale scores were
found not to differ significantly between phobic and nonphobic controls (M
difference 50.07, SE 50.13; p5n.s.).
Discussion
The present results suggest that emetophobia is associated with issues surrounding
locus of control. Most compellingly, not only did emetophobics endorse a much
greater internal locus of control with regard specifically to health issues than did
their phobic and nonphobic counterparts but emetophobics also endorsed a much
greater internal locus of control with regard to general issues. While controls both
with and without phobias yielded similar results, emetophobics considered most
aspects of their lives to be within their power and under their own command to a
greater degree than the nonemetophobics, as was hypothesized. While an internal
locus of control may have been more readily expected with regard to health locus of
control, especially since many emetophobics report a regular ability to control
vomiting, what is perhaps most compelling was the clear contention within
emetophobics that general events in life are also within their control. Although
not related directly to emetophobia, this nonetheless appears a significant trait
within the condition perhaps fueling one of emetophobia’s perpetuating features:
that of the need to have a feeling of control over all aspects of their lives.
It seems that emetophobics have a greater propensity to become anxious regarding
health-related issues than do nonemetophobics, but this level of anxiety permeates
across to other aspects of general living. Solomon, Holmes, and McCaul (1980)
investigated the relationship between anxiety and the ability to exert control over an
aversive event (i.e., the participant being threatened with the administration of
electric shocks). The findings indicated that a decrease in anxiety, similar to that
detected in those to whom no threat was posed, occurred in those only for whom
exerting control over an aversive event was easy and did not require too much effort
to exert. Participants for whom control was difficult to exercise reported a level of
anxiety concurrent with that experienced by those who could exert no control over
the identical aversive event. This highlighted primarily that control must be relatively
easy to achieve before anxiety surrounding abhorrent events can decrease. In
addition, such an ability to exercise control reduced physiological arousal exclusively
in the anticipatory period leading up to the event; however, during the actual
exercising of control over an aversive event, physiological arousal was not reduced.
Thus, it would seem that in certain circumstances, exercising control in dangerous or
unpleasant situations can increase physiological arousal such that it overrides any
initial advantage gained in the ability to take charge of a situation (Solomon et al.,
1980).
36 Journal of Clinical Psychology, January 2008
Journal of Clinical Psychology DOI 10.1002/jclp
Solomon et al. (1980) reasoned that in addition to control being difficult to
exercise and thus failing to reduce stress, so also does the controlling of an aversive
situation whereby most of the time is spent confronting or controlling rather than
anticipating. This would appear especially relevant in the case of emetophobia,
whereby considerable effort is indeed required to manage the situation (i.e.,
prevention of vomiting), which is a violent bodily reflex not experienced passively
(Andrews, 1992). The principle symptoms of emetophobia may arise from the fact
that since such patients fear losing control, they instead strive excessively to retain
command over a physical event which is naturally very difficult to control. In line
with Solomon et al.’s (1980) argument, the arousal subsequently generated is thus
greater than that created when no control exists, and although giving up would be
the adaptive choice; emetophobics appear completely unable to negate their
insatiable desire for the maintenance of control.
There exist three related features within learned helplessness: (a) an environment
in which some important outcome is beyond control, (b) the response of giving up,
and (c) the supplementary cognition which relates to the expectation that no
voluntary action can control the outcome (Seligman, 1992). It could be postulated
that emetophobics have an internal locus of control, reasoning events in life to be
within their power. It is therefore hypothesized that emetophobics may have an
intense fear of losing such control, as happens during the act of vomiting.
The present study was not without its flaws, and as the study developed, various
methodological issues arose which require consideration. Perhaps the greatest
problem was the disparity in demographic circumstances between the controls (both
phobic and nonphobic) and the emetophobics. A much greater proportion of
controls compared to the emetophobics were students, although around 50% of the
emetophobics had completed higher education. In addition, there was a significant
age gap between controls and emetophobics whereby, on average, emetophobics
were approximately 10 years older. While the majority of emetophobics were
American, most of the controls were British or Irish. Such issues may have
confounded the results since life experience may induce to an extent an increased
internal locus of control as individuals begin to take increasing charge of their future.
The Internet is well recognized as a valuable resource for conducting research into
psychiatric disorders (Childress & Asamen, 1998; Stones & Perry, 1997), although
support for the use of multidimensional scales on the Internet is weak (Hewson &
Charlton, 2005). A recent study did however find that Internet administration
of the Multidimensional Health Locus of Control scale yielded data that were found
to be at least as good as that of paper data (Hewson & Charlton, 2005). Note
that two different methods were adopted to collect the present data, whereby
the majority of data from emetophobics was collected electronically via the
Internet and the majority of data from the controls was collected via paper
copies of the study. The emetophobics therefore had no anonymity when submitting
their results.
Conclusion
This research has provided the basis for a range of future work to gain a thorough
insight into, and comprehension of, vomiting phobia and its association with an
internal locus of control.
Two fundamental traits of emetophobics arose from the current study: an internal
locus of control regarding both general and health-related issues. This article aimed
37Locus of Control in Vomiting Phobia
Journal of Clinical Psychology DOI 10.1002/jclp
to introduce control as a significant factor in emetophobia, about which future
research is required to build a more comprehensive framework of its predisposing,
precipitating, and perhaps most importantly, perpetuating factors. Thus far, it seems
reasonable to stipulate that individuals with a vomiting phobia deem events as being
within their control and may therefore find it difficult to relinquish this control
during the act of vomiting, thus inducing a phobia. As a starting point, it may be
useful for therapists to consider pathological issues related to control in cases of
vomiting phobia. Future research could further explore the association between fear
of vomiting and control.
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