Respondents
The ABN supplied a list of 634 names and addresses. Thirteen of these were
overseas and five were known by the authors to be non-neurologists (eg, one of
the authors of this paper), leaving 616 names. Three hundred and nineteen (52%)
responded to the first round, a further 57 responded to the second round, for an
aggregate response of 376 (62%), plus five that were returned ‘addressee
unknown’. Twenty-seven of these were not included in the analysis,
however, either because they did not complete the survey (n=7) or because
they gave us reason to exclude their responses. Reasons were: being a
neurophysiologist (n=8) or other non-neurologist (n=5); or being
retired (n=3), on long term sick leave (n=1) or otherwise not
seeing patients (n=3). Excluding those who were not practising
neurologists gave an adjusted completion rate of 349 from 591 eligible subjects
(59%). Although the incentives encouraged a response, they did not appear to
introduce a bias.
7In contrast with a previous survey of UK neurologists on this topic,
8 there were extensive comments and
amendments made by the respondents. These were sometimes simply complimentary
(“nice survey!”) or critical (“What do
you mean by conversion disorder?”) but
were often ‘running commentaries’ on the questions and
occasionally were extended responses—for example, in accompanying
letters.
Demographics and clinical background of the respondents (questions 1–5,
29) are given in . This reveals
them to be very largely male, of median late forties in age, overwhelmingly
trained in the British Isles, having worked for an average of 19.5 years
in neurology and, in 43% of cases, with some training in psychiatry or
neuropsychiatry. Female neurologists were marginally younger on average (median
in their early forties compared with late forties for men, p=0.02,
Mann–Whitney U test), with fewer years in neurology (median 14 vs
19 years, p=0.001, Mann–Whitney U test). Ten per cent of
neurologists reported having had a personal experience of CD before they studied
medicine, either in themselves, their family (most commonly their mother) or a
friend, with twice the proportion of neurologists trained in developing
countries (p=0.048, Fisher's exact test) having experienced CD in
their families. Prior experience of CD did not correlate with any particular
view, however, other than to make the neurologist more interested (as
demonstrated by their being more likely to describe cases or to expand on
‘other’ selections when offered the chance). The neurologists
reported seeing between one and 320 new patients per month but the upper bound
seemed implausible so we assumed that at least some of the respondents had
misread the question and have not considered it further.
| Table 1Demographic and clinical background of respondents' percentages
are of those answering the question rounded to the nearest whole
number |
The nature of conversion disorder
The responses to the questions on the nature of CD (questions 5–9,
11–15, 31) are given in .
They show that the great majority reported that patients with medically
unexplained symptoms comprised less than a quarter of their new referrals, and
that patients with CD were a minority of those, though almost a quarter thought
most of their unexplained patients had CD. Consistent with this, the most common
view was that CD was a particular subset of the unexplained, although more than
half saw it as a distinct, but perhaps overlapping, condition. When asked about
brief case vignettes, only 1% found the lack of apparent psychological problems
to preclude the diagnosis whereas 6% thought having only a minor tingle was not
sufficient and 17% thought that symptoms that were better when thought
unobserved could not possibly be CD.
| Table 2Neurologists' views on the nature of conversion disorder |
The most popular explanatory model was the Freudian-seeming
‘subconscious’, followed by the behavioural ‘abnormal
illness behaviour’, which were both far more commonly chosen than the
more neurological-seeming ‘disordered brain function’ or
‘effects of stress on the nervous system’—particularly so
for female neurologists (p=0.001, Fisher's exact test) where 40/60
(67%) preferred ‘subconscious’ explanations compared with 122/282
(43%) of male neurologists. Yet fewer than half of respondents thought
psychiatrists had a sufficient psychological explanation.
Explanations in terms of feigning were more nuanced: while the vast majority
thought only a few of their conversion patients were feigning, only a minority
saw the two as fully distinct, with most opting for a more entangled
relationship between conversion and feigning, including 13% who thought all of
their conversion patients were feigning, or vice versa. The nature of this
relationship was significantly determined by the age of the neurologist
(p=0.001, F=5.3) and the number of years they had practised
neurology (p<0.001, F=6.2), with older neurologists seeing the two
as less distinct. More broadly, this question seemed to identify clear subgroups
of neurologists. Those who thought conversion and feigning completely distinct
were unsurprisingly more likely (p<0.001,
χ2=36.9, df=6) to think that symptoms that
improved when thought unobserved precluded a diagnosis of CD and to think that
none of their conversion patients were feigning (p<0.001,
χ2=41.5, df=9). Contrasting these
neurologists with those who thought conversion to be just a type of feigning
showed the latter to be older (median late fifties, vs late forties,
p=0.01, Mann–Whitney U test) and more likely to have trained in
developing countries (p=0.019, χ2=5.5,
df=1). Their preferred model for conversion was in terms of abnormal
illness behaviour (p=0.003, χ2=19.5,
df=6) and they differed on their approaches to diagnosis and to
communication, as we discuss in those sections hereafter.
The neurologists were asked to give an example of a memorable case and 124 did
so, describing a range of presentations, most commonly weakness/paralysis
(n=46) or seizures (n=29). A qualitative rating of what was
distinctive about these cases was made. Where it was possible to reach a
judgement (109 cases), this was most commonly (37 cases) because they seemed
‘classic’ cases (life stressors leading to symptoms of a symbolic
or adaptive nature, such as a hand dystonia arising when having to sign an
important document) although often (28 cases) it was because of the dramatic
nature of the presenting symptom (such as sudden blindness) or of the patient or
their circumstances (15 cases) (such as being an ex-Special Forces soldier).
However, in 14 cases what seemed to have made it memorable was the apparent
deception or conscious control (such as a ‘paraplegic’ walking to
the bathroom when thought unobserved).
When asked whether CD was neurological in the same way that multiple sclerosis
was, 63% felt it was not and did not think that view would change. This was
answered differently by gender (p<0.001,
χ2=15.6, df=2) and by cultural background
(p=0.03, χ2=7.0, df=2), with 58% of
female neurologists and two-thirds of those trained in developing countries
either thinking that conversion was like multiple sclerosis or expecting to
think so one day.
Diagnosing conversion disorder
When it came to making the diagnosis, the majority felt they could do so very
(16%) or fairly (67%) confidently. They reported using the criteria in in making their diagnosis. This
showed that although the overwhelmingly favourite criterion was inconsistency,
and that ‘dislikeable’, ‘symptom severity’,
‘disability’ or ‘amount of work’ were the most
important for only a handful of neurologists, all of the characteristics were
endorsed as useful by substantial percentages of the neurologists: the more
‘psychiatric’ aspects of abnormal illness behaviour and
psychological abnormality were diagnostically important to large majorities, and
even the more personal ‘dislikeable’ and ‘amount of work
for you’ were endorsed by many. Observer dependence was middle weighted,
with 59% feeling it was useful—although this might either have been
useful in confirming conversion or in excluding the differential of feigning,
depending on the neurologist's view (see ). Those who thought conversion was merely a kind of
feigning were more likely to diagnose it on the basis of the amount of work the
patient caused them (p=0.001, χ2=30.7,
df=5) or the degree of disability they showed (p=0.048,
χ2=11.2, df=5), and less likely to base it
on the presence of psychiatric abnormality (p=0.043, Fisher's
exact test) than those who thought it a distinct entity.
| Table 3Diagnostic utility of patient characteristics |
Communication with patients
The neurologists' views on communicating with patients in this area
(questions 21–8) are given in . A slight majority (51%) thought that giving the diagnosis was
easier now than it was for those who trained them, although there was a
significant effect of age on this (p=0.03,
χ2=12.3, df=5), with every age group under 60
years finding it easier now, but those over 60 not finding it easier, by 4 to 1.
Most neurologists (97%) attempted to give an explanatory model to the patient if
asked, and if the patient seemed receptive, the neurologists would always (58%)
or usually (38%) talk about psychological factors. When the patient seemed
resistant, things slipped somewhat, with 17% saying they would rarely or never
discuss psychology. The model offered correlated well with the model the
neurologist believed (contingency coefficient=0.6, p<0.001), when
that model was restricted to stress, the subconscious or disordered brain
function, but those who believed feigning or abnormal illness behaviour best
explained CD did not present it to patients in those terms. Talking about
feigning was not popular, with only 18% always or usually addressing the issue
when it was suspected, and just under a third addressing it even when they were
certain the patient was feigning. This did not mean that the neurologists felt
it was not their responsibility—51% thought it was, with only 13%
thinking it should be ignored. The neurologist's gender proved a
significant determinant of communication preferences, with women more ready to
discuss psychological factors (p=0.019, χ2=7.9,
df=2) when the patient was receptive, or feigning when it was suspected
(p=0.049, χ2=7.9, df=3). Whereas the
majority of men found it no easier to give CD diagnoses today, women found it
easier by more than 2 to 1 (p=0.002, fisher's exact test). In
contrast, those who thought CD a special kind of feigning were much less likely
to discuss psychological factors (p=0.002,
χ2=12.1, df=2) with a receptive patient, and
more than 5 to 1 did not find it easier to talk about CD today (p=0.022,
Fisher's exact test) compared with those who thought CD and feigning
fully distinct.
| Table 4Neurologists' views on communication in conversion disorder and
feigning |
Neurologists were closely divided on the desirability of copying letters to
patients with CD. Just over a third always or usually used codes or euphemisms
when writing to the primary care physician (general practitioner
(GP))—with 79% doing so at least occasionally; the codes were most
commonly used to inform the GP that the patient had CD or a psychological
problem.