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6.1 INTRODUCTION 3
6.2 AIMS 3
6.3 QUESTIONS 3
6.4 METHOD 4
6.4.1 Participants 4
6.4.2 Measures 5Beck Anxiety Inventory (BAI; Beck, Epstein, Brown and Steer, 1988) 5Beck Depression Inventory (BDI; Beck, Ward, Mendelson, Mock and Erbaugh, 1961) 6Robson Self Concept Questionnaire (Robson, 1989) 6Illness Perception Questionnaire (IPQ; Weinman et al., 1996) 6Personal Beliefs about Illness Questionnaire (PBIQ; Birchwood et al, 1993) 8Distress Rating 9
6.4.3 Casenote Information 9
6.4.4 Procedure 9Recruitment 9Completing the questionnaires 10Analyses 10
6.5 RESULTS 11
6.5.1 Description of the Sample: Information at Time of Questionnaire Completion 11Sociodemographic information 11Clinical information 12
6.5.2 Information at Start of Illness 13Sociodemographic and clinical information 13
6.5.3 Reliability of Scales 13Reliability of the IPQ 13Reliability of the PBIQ 14
6.5.4 Distress and Self-esteem Scores 15
6.5.5 Illness Perception Measures 16
6.5.6 Association Between Measures 18Distress Measures 18Illness Perception Measures: IPQ 19Illness Perception Measures: PBIQ scales 21Illness Perception Measures: Relationship between IPQ scales and PBIQ scales 22
6.6 DISCUSSION 24
6.6.1 What are the rates of anxiety, depression and self-esteem? 24
6.6.2 How do people with psychosis view their illness? 25
Chapter 6 – Illness Appraisals in Psychosis 1
6.6.3 How do the illness appraisal measures relate to each other? 27
6.6.4 Conclusions 28
Chapter 6 – Illness Appraisals in Psychosis 2
CHAPTER 6. INVESTIGATION OF ILLNESS APPRAISALS IN
PSYCHOSIS: DESCRIPTION OF THE SAMPLE AND QUESTIONNAIRE
RESPONSES
6.1 INTRODUCTION
Investigation into factors associated with a single episode of illness detailed in
chapters three and four found that no factors at onset differentiated the group of
people with a single episode without residual symptoms from those with repeated
episodes without residual symptoms apart from a trend for insight to be better in the
single episode group. As outlined in the discussion section of chapter four, this raises
the possibility that psychological factors may play a part in outcome. The role of
illness appraisals in psychosis is described in the literature review in chapter five
which demonstrates that how a person thinks about their illness may contribute to
outcome in terms of symptoms and distress. As a result, it was decided to investigate
illness appraisals and distress in a heterogeneous group of individuals with psychosis.
6.2 AIMS
The principal aim of the study was to explore the relationship between illness
appraisal variables and distress. Three aspects of distress were examined: anxiety,
depression and low self-esteem. The results of this study are presented over two
chapters. The first of these (chapter six) is a description of the sample and their
responses on the measures, while the next chapter (chapter seven) is an investigation
of the association of illness appraisals and distress. As the results to be reported in
this chapter are exploratory and descriptive, no specific hypotheses have been made
and research questions are posed instead.
6.3 QUESTIONS
The following research questions are investigated.
1. What are the rates of anxiety, depression and self-esteem?
Chapter 6 – Illness Appraisals in Psychosis 3
Many of the studies outlined in chapter five have investigated rates of
comorbid depression. It would be of interest to determine the rates of all three
distress measures in one sample and to determine whether this sample is
consistent with other cross-sectional samples of people with schizophrenia. In
addition, it would be informative to investigate the associations between these
measures of distress.
2. How do people with psychosis view their illness?
The literature review in chapter five describes some relationships between
illness perceptions and distress. However, this research is still in its infancy
and little is known about the particular illness beliefs held by people with
psychosis. It would be interesting, for example, to have a better
understanding of which causal beliefs are endorsed by people with psychosis,
and to determine which illness appraisals occur in a large sample of people
with schizophrenia or schizophrenia-related disorders.
3. How do the illness appraisal measures relate to each other?
No study to date has used measures of illness representation described by the
Self-Regulation Model (Leventhal et al., 1980) alongside measures from
psychological approaches to psychosis (in this case, the Personal Beliefs about
Illness Questionnaire; Birchwood et al., 1993). It is of interest to examine
how the measures relate to one another.
6.4 METHOD
6.4.1 Participants
Broad criteria for inclusion into the study were established in order to include people
with a range of distress associated with their illness and a range of symptom
presentations and outcomes. Participants were required to have a primary case-note
diagnosis of a functional psychosis, according to International Classification of
Diseases-10 (F20 – schizophrenia; F25 – schizoaffective disorder; F22 – delusional
disorder; F23.8 – brief psychotic disorder; F29 – psychotic disorder, not otherwise
specified, ICD-10; World Health Organisation, 1992) or to have had symptoms
Chapter 6 – Illness Appraisals in Psychosis 4
consistent with the above in the absence of a written diagnosis. Illness length could
be of any duration and there was no requirement for individuals to be experiencing
current psychotic symptoms. In order to ensure participants could understand the
information sheet and the questionnaires, it was requested that people with very low
intellect or poor understanding of English be excluded from consideration for the
study. It was not essential for individuals to be able to read fluently or to write as the
questionnaires could, if needed, be read to them.
Staff in two mental health trusts suggested the names of four-hundred and seven
people over the course of the study and attempts were made to contact all of these
individuals. Sixty-one were unsuitable for the study and it was not possible to trace
13 people. Three hundred and thirty-three participants were potentially suitable, of
whom 159 refused to take part. One hundred and seventy-four individuals, therefore,
participated in the study (52.3% of those who were potentially suitable). All
participants were in current contact with psychiatric services; 119 were known to
Oxfordshire Mental Healthcare NHS Trust and 55 to North East London Mental
Health NHS Trust. Participants were asked to attempt to complete the whole package
of questionnaires. Two individuals, both from Oxfordshire, changed their minds
about completing the study after giving consent and were excluded from the total.
6.4.2 Measures
The package of questionnaires incorporated the following self-report measures:
Beck Anxiety Inventory (BAI; Beck, Epstein, Brown and Steer, 1988)
This is a 21 item checklist of symptoms of anxiety widely used in both clinical
practice and research. The individual is asked to indicate how much they have been
bothered by the symptoms in the last week, choosing from four options ranging from
“Not at all” to “Severely, I could barely stand it”. These are scored 0-3 resulting in a
total BAI score of 0-63, with high scores indicating higher anxiety. The scale has
good internal reliability and test-retest consistency (Beck et al., 1988)
Chapter 6 – Illness Appraisals in Psychosis 5
Beck Depression Inventory (BDI; Beck, Ward, Mendelson, Mock and Erbaugh, 1961)
This is the most widely used self-report measure of depression, with items relating to
physiological, cognitive and behavioural symptoms of depression. For each of the 21
items, the individual is asked to choose one statement which best describes how they
have been feeling in the last week from a group of four of increasing severity. The
items are scored 0-3 resulting in a total BDI score of 0-63 with high scores indicating
more severe depression. The scale has good test-retest reliability (Beck et al., 1988)
and high levels of internal consistency (e.g. Strober et al., 1981).
Robson Self Concept Questionnaire (Robson, 1989)
This is a 30-item questionnaire for assessment of self-esteem with good reliability
and validity. Defining self-esteem as a composite and not single entity, the scale
assesses seven components of self-esteem: subjective sense of significance;
worthiness; appearance and social acceptability, competence, resilience and
determination; control over personal destiny and the value of existence. The
individual is asked to indicate how much they agree or disagree with each statement,
according to how they typically feel. The answers are scored on a scale of 0-7 and a
total score is calculated. A high score represents high self-esteem, with 140 being
considered the “normal” mean with a standard deviation of 20 (Romans et al., 1996;
Robson, 1989). This measure has been used previously in studies with people with
psychosis (e.g. Close and Garety, 1998; Freeman et al., 1998) and correlates highly
with Rosenberg’s (1965) measure of self-esteem (Robson, 1989).
Illness Perception Questionnaire (IPQ; Weinman et al., 1996)
Having found that the five components of illness representation described by
Leventhal’s self-regulation model (Leventhal et al., 1984) are valid and consistent
across a range of different clinical conditions (Skelton and Croyle, 1991), the IPQ
was developed to assess each of these cognitive representations. The measure
consists of five subscales covering themes of illness identity (ideas about the labels
for the symptoms of illness), cause (ideas about the likely causes of illness), time-line
(the likely duration of illness and whether acute, chronic or episodic), consequences
(beliefs about the illness severity and effect on physical, social and psychological
functioning) and cure/control (beliefs about the extent to which the illness is
Chapter 6 – Illness Appraisals in Psychosis 6
amenable to improvement). The questionnaire shows good internal consistency and
re-test reliability (Weinman et al., 1996), and has been used in a wide variety of
conditions including heart disease (e.g. Cooper et al., 1999), diabetes (Griva et al.,
2000) and in carers of people with major health problems (e.g. Heijmans et al., 1999).
The identity subscale comprises a list of core symptom items that the person is
required to rate for frequency on a four point scale ranging from “All of the time” to
“Never” according to how often the individual experiences the symptom as part of his
or her illness. This can be scored 0-3 to give a frequency of symptoms, or rated 0 or
1 to give a total number of symptoms. The other subscales are rated on a five-point
scale ranging from “Strongly Disagree” to “Strongly Agree”, scored 1 to 5. After
reverse-scoring the appropriate items, scores for the time-line, consequences and
cure/control scales can be achieved by summing the totals. Time-line consists of
three items, giving a score of 3-15. The consequences scale comprises seven items
giving a score of 7-35, and cure-control scale consists of six items, giving a total
score of 6-30. The cause scale consists of eleven items which should not be
aggregated as each item refers to a specific causal belief. It may, however, be
appropriate to combine items to consider particular factors such as internal or
external causes (Weinman et al., 1996).
As the IPQ was designed for a physical health environment, the identity section of the
original did not include symptoms relating to the acute exacerbation of a psychotic
disorder. The original symptom list
“incorporated twelve common symptoms from other
symptom checklists… This core list of items may be added
to by researchers to tailor the scale to specific illnesses”
(Weinman et al., 1996, p.433)
The identity section of the IPQ used in this study was developed by Weinman and
Garety (reported in Bucher, 1998, unpublished BSc thesis) to include core symptoms
of a psychotic disorder as well as most general non-psychotic symptoms. In addition,
the IPQ was originally developed for a physical health environment and refers
throughout to “illness”, thus suggesting a medical model. It is quite likely that some
individuals with a mental health problem will not perceive their difficulties as
representing an illness, and so the questions were changed throughout to state
Chapter 6 – Illness Appraisals in Psychosis 7
“problems/illness” (Weinman et al, personal communication). Use of this amended
questionnaire with people with psychosis has been validated by a number of further
studies (Jolley, Garety and Bucher, in preparation; Watson et al, in preparation). A
different revised version of the IPQ (IPQ-R; Moss-Morris et al., 2002) with an
extended identity section has been used by Lobban and colleagues in individuals with
schizophrenia (Lobban, Barrowclough and Jones, 2003) and in carers of individuals
with psychosis (Barrowclough et al., 2002).
A copy of the IPQ can be found in appendix XX.
Personal Beliefs about Illness Questionnaire (PBIQ; Birchwood et al, 1993)
This is a 16-item measure consisting of 5 subscales designed to assess how much
individuals with a diagnosis of psychosis believe certain social and scientific
statements about mental illness. Birchwood et al. (1993) describe:
“Belief in ‘self as illness’ assesses the extent to which
subjects believe that the origins of their illness lies in their
personality or psyche and includes four questions; ‘control
over illness’ [later renamed “entrapment”] includes four
questions and assesses the extent to which subjects feel they
have control over their illness; ‘stigma’ [later renamed “self
humiliation and shame”] includes three questions assessing
whether subjects believe their illness is a social judgement
upon them; ‘social containment’ [later renamed “social
humiliation”] assesses subjects’ belief in social segregation
and control of the mentally ill and includes two questions;
and finally ‘expectations’ [later renamed “loss”] assesses
whether they feel the illness affects their capacity for
independence.” (Birchwood et al., 1993, p.389).
Each question is rated on a four-point scale, with low scores indicating more positive
attitudes towards the self and psychosis, meaning low awareness of stigma, higher
control over illness and positive views of self-efficacy. A copy of the PBIQ can be
seen in appendix XX.
Chapter 6 – Illness Appraisals in Psychosis 8
The scales were described to have reasonable internal consistency and good test-
retest reliability (Birchwood et al., 1993).
6.4.3 Casenote Information
Casenotes were examined after completion of the questionnaires for those who
consented. Three people (1.7%) refused consent to look at their notes, and notes for
one person were missing in their entirety.
In order to enable testing of hypotheses arising from the first study (reported in
chapter 4), information was sought both for first contact with a psychotic illness and
at time of questionnaire completion. Information at first contact with mental health
serves with a psychotic disorder was gathered, where possible, on the same variables
as in the first study, with the exception of durations of untreated psychosis and
prodrome and presence of an identifiable trigger to illness due to the inadequacy of
information on this.
6.4.4 Procedure
Recruitment
Potential participants were identified by care-coordinators in Community Mental
Health Teams and Rehabilitation Services across Oxfordshire Mental Healthcare
NHS Trust and North East London Mental Health NHS Trust, after appropriate
ethical approval had been granted. Once individuals meeting the diagnostic criteria
had been identified by the care-coordinators, there were various ways of proceeding.
Some individuals were invited to take part in the study by letter from the author
including an information sheet, response sheet and stamped, self-addressed envelope.
Some were contacted by telephone, and those in inpatient units were contacted in
person. In some cases the individuals were asked by their care-coordinators either to
take part or for permission for the author to contact them.
Completing the questionnaires
Having expressed an interest to take part in the study, telephone contact was usually
made with the participants at which time it was decided whether to meet to fill in the
Chapter 6 – Illness Appraisals in Psychosis 9
questionnaires, or to do it by post. In a small number of cases (n=15, 8.7%), the care-
coordinator competed the questionnaires with the participant, without any contact
from the author. If the person chose to complete the questionnaires by post, issues of
consent were discussed on the telephone and they signed the consent form at the time
of completing the questionnaire. If meeting, consent was discussed in person prior to
the completion of the questionnaires. 23 (13.4%) opted to complete the
questionnaires by post while the remaining participants (n=134, 77.9%) met with the
author either at their home or in a Mental Health setting.
Participants in North East London Mental Health NHS Trust (NELMHT) received
£10 for taking part in the study. This was as a result of two main factors: the
recruitment in NELMHT being alongside recruitment for another study for which
people were being paid, and to aid the rate of recruitment.
Analyses
Descriptive information was generated by SPSS version 11.0 (SPSS Inc, 2001).
In order to investigate the relationship between the questionnaire measures,
correlations were conducted between the variables using SPSS. Depending on the
distribution of the data, Pearson’s Product Moment correlations or Spearman’s rho
correlations were calculated, all with two-tailed significance.
Missing data were treated in two ways. When missing from the casenote information
it was left as missing. When questionnaire information was missing for the items on
scales or subscales, scores were prorated when appropriate to do so. For scales with
three items, information had to be present for two in order to prorate. For scales with
more items, at least 75% of the items were required to be endorsed.
It should be noted that a number of correlations were conducted resulting in the
potential for Type I error: finding something to be of significance when it was not.
Significance levels were not adjusted for multiple testing.
All analyses were conducted using SPSS version 11.0.
Chapter 6 – Illness Appraisals in Psychosis 10
6.5 RESULTS
Descriptive information about the sample is presented first, followed by issues of
reliability of the scales and details of the responses on the measures. Finally,
analyses investigating the correlations between the illness perception and distress
measures are presented.
6.5.1 Description of the Sample: Information at Time of Questionnaire
Completion
Sociodemographic information
Of the 172 participants who completed the study, 117 (68.0%) were male and 55
(32.0%) were female. The mean age at the time of completing the questionnaire was
41.7 years (SD=12.0). Twenty-one (27.3%) were inpatients with an acute episode of
psychotic illness when seen, 127 (74.3%) were living independently, 36 (21.2%)
were living in supported accommodation and 8 (4.7%) were staying in a
rehabilitation unit. Twenty-six (15.3%) were married, 116 (68.2%) were single, 24
(14.1%) were divorced or separated and 4 (2.4%) had been widowed. Twenty
(12.1%) were employed, 136 (82.4%) were unemployed, 3 (1.8%) were students and
6 (3.6%) were doing voluntary work.
For the 164 individuals for whom premorbid adjustment information was available,
143 (87.2%) had no premorbid adjustment difficulties, 9 (5.5%) had some degree of
difficulty and 12 (7.3%) had marked difficulties. Information on educational
attainment was available for 129 (75.0%) of the sample. Of these, 42 (32.6%) had no
qualifications, 47 (36.4%) had passed ‘O’Levels or equivalent, 22 (17.1%) had
passed ‘A’Levels and 18 (14.0%) had gained a degree or higher degree by the time of
the questionnaire completion.
Seventy-three (50.7%) had no family history of mental illness recorded in the
casenotes, 15 (10.4%) had a history of psychosis, 41 (28.5%) had a history of anxiety
or depression. Fifteen (10.4%) had a family history of psychiatric illness, the
diagnosis of which was either unknown or inconclusive, for example “mother had a
breakdown”.
Chapter 6 – Illness Appraisals in Psychosis 11
Clinical information
Of the total sample of 172, date of onset was available for 164. This sample had a
mean of 14.4 years since first onset of psychotic illness (SD=10.9, n=164) with a
range of 0 to 38 years. They had had a mean of 3.3 admissions since the start of
illness (SD=3.1, n=158) of which 1.2 (SD=1.7, n=111) had been in the last 6 years.
Four (2.4%) were in their first episode of illness, 113 (72.4%, n=156) had a history
over 6 years’ duration. Schizophrenia was the most common diagnosis with 102
(61.4%) having this casenote diagnosis. The remaining 64 for whom information
was available had diagnoses of schizoaffective disorder (n=36, 21.7%), psychotic
episode (n=22, 13.3%) or had no psychotic diagnosis, but had experienced symptoms
consistent with such a disorder (n=6, 3.6%). Of the 165 cases for whom information
was available, 157 (95.2%) were prescribed an antipsychotic medication at the time
of meeting. Fifty-seven (36.5%, n=156) had been admitted under Mental Health Act
section at least once during the course of their illness while 14 (8.9%, n=158) had
never been admitted. Examination of the casenotes for the 172 participants found
them to have the following patterns of illness course (shown in Table X).
Fifty-five (33.1%, n=166) had a history of self-harm reported in the notes and 43
(25.0%, n=168) were reported to have current drug or alcohol abuse.
Table X. Pattern of illness course at time of questionnaire completion Frequency (N) Percent
Repeated episodes no persistent residual symptoms
83 48.3
Repeated episodes with persistent residual symptoms
64 37.2
Single episode no persistent residual symptoms 7 4.1
Single episode with persistent residual symptoms 9 5.2
Seen in first episode 4 2.3
Unable to determine 5 2.9
Total 172
Chapter 6 – Illness Appraisals in Psychosis 12
6.5.2 Information at Start of Illness
Sociodemographic and clinical information
The mean age at first illness presentation was 27.3 years (SD=8.5, n=164). Marital
status was different from that at questionnaire completion, with 123 (75.9%) being
single, 29 (17.9%) married and 10 (6.2%) divorced or separated. Forty-five (34.6%)
were employed at the start of their illness, 69 (53.1%) were unemployed and 16
(12.3%) were in full time education.
6.5.3 Reliability of Scales
Reliability of the IPQ
On the recommendation of J. Weinman and supported by recent analysis of the IPQ
(Moss-Morris et al., 2002), tests of internal reliability were conducted on the IPQ.
Timeline had a high internal reliability coefficient (Cronbach’s alpha=0.87, N=172)
and was therefore kept in its original state. Consequences had an internal reliability
of 0.60, improving to 0.66 with the deletion of item 17 (n=166; “My current
problems/illness have become easier to live with”). Cure/Control had a Cronbach’s
alpha of 0.57 (n=165), improving to 0.66 with the deletion of items 25 (“My
treatment will be effective in curing my current problems/illness”) and 26 (“Recovery
from my current problems/illness is largely dependent on chance or fate”). In order
to maximise the internal consistency of the scales, the item-deleted scales were used
for analyses. Comparison of the descriptives for these scales is given below. In
future the revised item-deleted scales will be referred to as “Consequences” and
“Cure/Control”.
Table X. Internal reliability of IPQ Consequences and Cure/Control Scales
Variable Number of items
Total N Mean SD
IPQ Consequences with item 17 7 172 25.1 4.3
IPQ Consequences without item 17 6 172 22.7 4.1
IPQ Cure/Control with items 25 and 26 6 172 20.0 4.1
IPQ Cure/Control without items 25 and 26 4 171 13.4 3.3
Chapter 6 – Illness Appraisals in Psychosis 13
In addition, in accordance with the statement of Weinman et al. (1996) that it may be
appropriate to combine causal items to look at factors such as internal and external
causes, exploratory factor analyses were conducted. Five factors were suggested:
germ/virus, diet and pollution; personality and own behaviour; state of mind, stress
and others; poor medical care; heredity and chance. The scales suggested by the
factor analyses, had low internal reliability (Cronbach’s alpha <0.6) and one factor
had only one item. In view of this it was decided to use the causal items of the IPQ
singly. In accordance with the suggestion by Weinman (2004, personal
communication) that it was sensible to “concentrate on those items where there was a
reasonable spread of agreement/disagreement in the sample”, the causal items of
germ/virus and pollution were excluded from the analyses in view of their very low
endorsement (less than 10%).
Reliability of the PBIQ
As checks for reliability were made for the IPQ, it was decided that similar checks
should be made for the internal reliability of the PBIQ scales. The original internal
reliability of the scales is shown below (Birchwood et al., 1993) alongside those of
the present study.
Table X. Internal reliability of PBIQ scales
In the current study, the social humiliation and self humiliation subscales had
unacceptably low Cronbach’s alphas; social humiliation was notably low at 0.04.
The social humiliation subscale consists of the two items “Because of my illness, I
have to rely on psychiatric services” and “Society needs to keep people with my
illness apart from everyone else”. In this population there was no association
between the two items, with 127 people (74.3%) agreeing with the first statement and
only 19 (11.2%) agreeing with the second.
Chapter 6 – Illness Appraisals in Psychosis
Entrapment Self humiliation
Self as illness
Social humiliation
Loss
Number of items 4 3 4 2 3
Birchwood et al. Cronbach’s alpha 0.64 0.61 0.71 0.51 0.58
Current study: Cronbach’s alpha 0.74 0.42 0.56 0.04 0.61
14
In view of some of the low Cronbach’s alpha scores in this study, a factor analysis
was conducted to determine whether a different arrangement of the items would
produce more coherent subscales for this population. Factor analysis produced five
factors with the same number of items in the scales as the original questionnaire.
Internal reliability of these items had a range of Cronbach’s alphas from 0.54 to 0.71.
While this was a better range of reliability than that of the original scales for this
sample, the groupings of items were difficult to identify as meaningful entities. For
example, “I am fundamentally normal, my illness is unlike any other” was put
together with “I find it difficult to cope with my current symptoms” as one factor. In
addition, reorganising the items would make it difficult to compare the results of the
current study with others. Similarly, although treating all 16 items of the
questionnaire as one scale had an excellent internal reliability Cronbach’s alpha of
0.83, it was felt that this would be difficult to interpret meaningfully. For this reason
it was decided to retain the original subscales, but as the original scales had a range of
internal consistency scores from 0.71 to a lowest Cronbach’s alpha of 0.51, it was
decided to use 0.5 as the minimum acceptable limit. As a result, analyses were
limited to the subscales of Entrapment, Self as illness and Loss.
6.5.4 Distress and Self-esteem Scores
The means, standard deviations and quartiles for the measures of anxiety, depression
and self-esteem are displayed in Table X.
Table X. Scores on distress items
Variable Total N Range Mean SD Median Quartiles25% 75%
Beck Anxiety Inventory 172 0-53 14.0 10.5 11.0 6.0 20.0
Beck Depression Inventory 172 0-50 16.5 11.3 13.5 7.3 23.0
Robson SCQ 172 38-210 114.8 32.7 113.0 97.0 134.0
The mean scores of the BDI and BAI suggest the population suffered from mild-
moderate anxiety and depression. The mean score on the Robson SCQ is over one
standard deviation lower than the mean of Robson’s non-clinical group (1989),
suggesting lowered self-esteem in the current sample. The standard deviation of 32.7
is greater than that in Robson’s (1989) sample of 20. According to the original cut-
Chapter 6 – Illness Appraisals in Psychosis 15
offs for depression (Beck et al., 1961), 56 (32.6%) people were in the normal range
for depression, 50 (29.1%) suffered mild-moderate depression, 43 (25.0%) suffered
moderate-severe depression and 23 (13.4%) suffered with severe depression. Using
the norms for anxiety (Beck et al., 1988), 74 (43%) scored in the normal range for
anxiety, 46 (26.7%) scored in the mild-moderate range, 34 (19.8%) scored in the
moderate-severe range and 18 (10.5%) scored in the severe range.
Using Birchwood and colleagues’ cut-off of 15 or above on the BDI to suggest at
least mild depression, 83 people (48.3%) suffered from depression. Using 15 or
above for anxiety, 67 people (39.0%) suffered from anxiety.
6.5.5 Illness Perception Measures
The scores on IPQ scales and PBIQ scales are detailed separately below. The
responses on the cause subscale of the IPQ are displayed in Table X, showing the
pattern of agreement with each of the possible cause items. Details of the other IPQ
subscales are shown in Table X. As can be seen, the identity section of the IPQ was
limited to psychotic symptoms. This was in order not to overlap with more general
symptoms such as lack of concentration which may be assessed by the measures of
anxiety and depression. The individual components of the Identity scale are outlined
in Table X.
PBIQ scores are shown in Table X.
Table X. IPQ Cause items
Variable Total N
Mean SD Agree (%) Neither agree nor disagree (%)
Disagree (%)
IPQ Cause: state of mind 171 3.7 1.2 126 (73.7) 13 (7.6) 32 (18.7)
IPQ Cause: heredity 171 2.8 1.3 56 (32.7) 41 (24.0) 74 (43.3)
IPQ Cause: chance 171 3.1 1.4 78 (45.6) 25 (14.6) 68 (39.8)
IPQ Cause: personality 172 3.4 1.3 102 (59.3) 24 (14.0) 46 (26.7)
IPQ Cause: stress 172 4.0 1.1 140 (81.4) 12 (7.0) 20 (11.6)
IPQ Cause: poor medical care 172 2.4 1.3 39 (22.7) 32 (18.6) 101 (58.7)
IPQ Cause: diet 172 2.1 1.2 30 (17.4) 20 (11.6) 122 (70.7)
IPQ Cause: germ/virus 172 1.8 1.0 15 (8.7) 21 (12.2) 136 (79.1)
IPQ Cause: pollution 171 1.8 1.0 12 (7.0) 21 (12.3) 138 (80.7)
Chapter 6 – Illness Appraisals in Psychosis 16
IPQ Cause: own behaviour 172 2.9 1.2 64 (37.2) 33 (19.2) 75 (43.6)
IPQ Cause: others 170 3.4 1.3 91 (53.5) 34 (20.0) 45 (26.5)
As illustrated above, particular patterns emerge for the appraisal of cause in
psychosis. Fewer than 10% agreed with the statements that their illness was caused
by a germ/virus or pollution, with around 80% disagreeing, indicating that these
causes are not perceived to be relevant for people with psychosis. Stress was
endorsed strongly by the sample (81.4%) as was state of mind (73.7%) and
disagreement with the statement that diet was a cause (70.7%). Own behaviour as a
cause of illness showed a spread of agreement with 37.2% agreeing and 43.6%
disagreeing and chance showed a similar spread of agreement (45.6% versus 39.8%).
Heredity had the highest percentage of people answering that they did not know
(24.0%). Others and personality showed similar patterns of agreement with one
another, with the majority of people agreeing, while the majority of the participants
(58.7%) disagreed that poor medical care contributed to their illness. Interestingly,
however, 22.7% felt that poor medical care did play a part.
Table X. IPQ scales: Identity, Timeline, Consequences and Cure/ControlVariable Total N Mean SD Median Quartiles
25% 75%IPQ Identity / Frequency of psychotic symptoms 167 5.3 4.3 5.0 2.0 8.0
IPQ Timeline 172 10.9 3.2 11.5 9.0 13.8
IPQ Consequences 172 22.7 4.1 23.0 20.0 26.0
IPQ Cure/Control 172 13.4 3.3 14.0 12.0 16.0
Table X indicates that the group endorsed low rates of positive symptomatology,
given the possible range of scores of 0-18 and that 75% of the sample had scores of 8
or below. Timeline had a range of scores of 3-15, suggesting that the sample
perceived a long duration of illness. Similarly, scores on the Consequences scale
suggest the sample generally perceived negative consequences of illness and scores
of appraisal of control over illness suggest the sample held low beliefs in its
controllability.
Table X. Individual components of Identity scale
Chapter 6 – Illness Appraisals in Psychosis 17
Symptom N Range Mean SD Endorsed (%)
Hearing voices 172 0-3 0.91 1.07 51.7
Feeling controlled by others 171 0-3 0.96 1.02 57.3
Seeing images 172 0-3 0.55 0.82 36.6
Having paranoid thoughts 172 0-3 1.10 1.01 64.5
Holding beliefs not shared by others 167 0-3 1.14 1.08 64.7
Feeling that my mind is being controlled 172 0-3 0.74 0.98 44.2
Although the sample reported low frequency of symptoms, Table X indicates that a
substantial percentage of the sample reported positive symptoms at least
“occasionally”, with half the sample reporting auditory hallucinations and 65 percent
reporting paranoid thoughts.
Table X. PBIQ scalesVariable Total N Mean SD Median Quartiles
25% 75%
PBIQ Entrapment 170 10.0 2.8 10.0 8 12.0
PBIQ Self as illness 171 9.7 2.5 10.0 8.0 11.0
PBIQ Loss 171 7.6 2.1 8.0 6.0 9.0
The PBIQ scale scores outlined in Table X indicates that Entrapment is evenly
distributed with the mean and median being equivalent to the actual mean of the
scale. Self as illness is similarly distributed, as is PBIQ Loss.
6.5.6 Association Between Measures
Distress Measures
Using Pearson’s Product Moment Correlation, all three distress measures were
significantly correlated with each other. Anxiety and depression had a correlation
coefficient of 0.61 (N=172, p<.001, two-tailed test), while anxiety was negatively
correlated with self-esteem (r= -0.46, N=172, p<.001). Depression and self-esteem
were negatively correlated (r= -0.74, N=172, p<.001). Increased anxiety was
associated with increased depression and that high self-esteem was associated with
Chapter 6 – Illness Appraisals in Psychosis 18
lower anxiety and depression. The correlation between anxiety and self-esteem
shows a medium effect size while the correlations between depression and anxiety
and depression and self-esteem show large effect sizes (Cohen, 1988, cited in Clark-
Carter, 1997).
Illness Perception Measures: IPQ
Cause subscale: As the cause items were to be assessed individually, and the factor
analyses of the items have already been reported, correlations between the cause
subscale items were not conducted.
Timeline, Consequences, Cure/Control and Identity subscales: The IPQ subscales of
Timeline, Consequences, Cure/control and Identity (frequency of psychotic
symptoms) all showed significant correlations with one another. These are shown in
Table X. The strongest effect is that shown by timeline and consequences, indicating
that the longer the perceived duration of illness, the greater the perceived
consequences of illness. Greater perceived cure/control was associated with shorter
perceived duration of illness and fewer negative consequences. Greater number of
symptoms was found to be related to longer perceived duration of illness, greater
perceived consequences and lower sense of cure/control. The actual duration of
illness was also examined for correlations with the IPQ, including IPQ Timeline,
which had no relationship (r=0.08). None of the subscales was related to actual
length of illness.
Table X. Correlations between IPQ scales
IPQ timeline IPQ consequences
IPQ cure/control
IPQ identity
IPQ Consequences
Pearson Correlation 0.40**
Sig. (2-tailed) <0.001
N 172
IPQ Cure/Control
Pearson Correlation -0.25** -0.17*
Sig. (2-tailed) 0.001 0.025
N 171 171
IPQ Identity Pearson Correlation 0.26** 0.31** -0.34**
Chapter 6 – Illness Appraisals in Psychosis 19
Sig. (2-tailed) 0.001 <0.001 <0.001
N 167 167 166
Years since illness start
Pearson Correlation 0.08 -0.02 -0.13 0.01
Sig. (2-tailed) 0.305 0.814 0.100 0.857
N 164 164 163 159
** Correlation is significant at the 0.01 level (2-tailed).* Correlation is significant at the 0.05 level (2-tailed).
The IPQ cause scales and the IPQ Consequences, Cure/control, Timeline and Identity
scales show the associations below (Table X). As can be seen, a number of the
variables are significantly correlated with each other, mainly showing small effect
sizes. Of interest, IPQ identity was associated with agreeing with own behaviour and
state of mind as playing a part in causing illness, while the causes of illness
personality, stress, state of mind and others were all associated with greater perceived
consequences of illness. Heredity and others were both associated with greater
timeline, while diet was found to be associated with lower reported consequences of
illness.
Table X. Correlation coefficients IPQ subscales (Spearman’s rho)
IPQ identity IPQ timeline
IPQ consequences
IPQ cure/control
IPQ cause: diet Correlation Coefficient 0.14 0.05 -0.17* -0.02
Sig. (2-tailed) 0.065 0.479 0.027 0.769N 167 172 172 171
IPQ cause: heredity
Correlation Coefficient 0.10 0.24** 0.08 <0.01
Sig. (2-tailed) 0.214 0.002 0.315 0.961N 167 171 171 170
IPQ cause: chance
Correlation Coefficient 0.08 0.00 -0.02 -0.01
Sig. (2-tailed) 0.299 0.998 0.777 0.944N 166 171 171 170
IPQ cause: personality
Correlation Coefficient 0.17* 0.13 0.20** 0.12
Sig. (2-tailed) 0.026 0.093 0.008 0.109N 167 172 172 171
IPQ cause: stress Correlation Coefficient -0.03 0.05 0.25** 0.14
Sig. (2-tailed) 0.724 0.507 0.001 0.076N 167 172 172 171
IPQ cause: own behaviour
Correlation Coefficient 0.22** -0.09 -0.02 0.09
Sig. (2-tailed) 0.004 0.223 0.835 0.265
Chapter 6 – Illness Appraisals in Psychosis 20
N 167 172 172 171IPQ cause: others Correlation
Coefficient 0.15 0.18* 0.30** 0.01
Sig. (2-tailed) 0.059 0.021 <0.001 0.849N 165 170 170 169
IPQ cause: poor medical care
Correlation Coefficient 0.01 -0.09 0.06 -0.11
Sig. (2-tailed) 0.896 0.234 0.462 0.164N 167 172 172 171
IPQ cause: state of mind
Correlation Coefficient 0.17* 0.06 0.32** 0.06
Sig. (2-tailed) 0.024 0.406 <0.001 0.423N 167 171 171 170
** Correlation is significant at the 0.01 level (2-tailed).* Correlation is significant at the 0.05 level (2-tailed).
Illness Perception Measures: PBIQ scales
The three subscales of the PBIQ were significantly correlated with each other as
shown in Table X. Entrapment showed a moderate association with Self as illness
and a large association with Loss. Loss and Self as illness were also significantly
correlated with one another, showing a medium effect size.
** Correlation is significant at the 0.01 level (2-tailed).* Correlation is significant at the 0.05 level (2-tailed).
Illness Perception Measures: Relationship between IPQ scales and PBIQ scales
The pattern of association between the IPQ and PBIQ are in Tables X and X. As can
be seen in the first table (Table X), all of the illness perception subscales from the
IPQ and PBIQ are significantly correlated with each other, in the expected direction.
For example, higher scores on PBIQ entrapment are associated with lower perceived
Chapter 6 – Illness Appraisals in Psychosis
PBIQ entrapment
PBIQ self as illness
PBIQ loss
PBIQ Self as illness Pearson Correlation 0.46**
Sig. (2-tailed) <0.001N 170
PBIQ Loss Pearson Correlation 0.55** 0.40**
Sig. (2-tailed) <0.001 <0.001N 170 171
Years since illness began
Pearson Correlation -0.04 0.10 0.18*
Sig. (2-tailed) 0.645 0.224 0.019N 162 163 163
21
IPQ cure/control, longer timeline and greater perceived consequences. In addition,
greater scores on PBIQ entrapment were associated with higher IPQ identity
indicating that greater symptom frequency correlated with greater perceived
entrapment. PBIQ loss was significantly related to longer perceived duration of
illness, greater frequency of symptom, poorer sense of cure/control and greater
perceived negative consequences of illness.
Table X. Correlations between IPQ scales and PBIQ scales
IPQ timeline
IPQ consequences
IPQ cure/control
IPQ identity
PBIQ entrapment Pearson Correlation 0.25** 0.37** -0.49** 0.41**
Sig. (2-tailed) 0.001 <0.001 <0.001 <0.001N 170 170 169 165
PBIQ self as illness
Pearson Correlation 0.35** 0.32** -0.34** 0.42**
Sig. (2-tailed) <0.001 <0.001 <0.001 <0.001N 171 171 170 166
PBIQ loss Pearson Correlation 0.43** 0.33** -0.42** 0.35**
Sig. (2-tailed) <0.001 <0.001 <0.001 <0.001N 171 171 170 166
** Correlation is significant at the 0.01 level (2-tailed).* Correlation is significant at the 0.05 level (2-tailed).
Looking at the PBIQ and its association with the cause section of the IPQ reveals a
number of significant correlations all showing small effect sizes. Greater agreement
with heredity as a cause of illness was associated with greater loss (PBIQ loss), while
the belief that others caused the individual’s illness was associated with greater PBIQ
entrapment and PBIQ loss. PBIQ loss was also found to be associated with poor
medical care as a cause of illness, and belief that diet was a cause. PBIQ self as
illness was associated with seeing one’s personality as a cause of illness, as was
believing one’s state of mind to be a causative factor.
Table X Correlation coefficients between PBIQ subscales and IPQ identity
(Spearman’s rho)
PBIQ entrapment
PBIQ self as illness
PBIQ loss
IPQ cause: diet Correlation Coefficient 0.20** 0.16* 0.15*Sig. (2-tailed) 0.008 0.035 0.050N 170 171 171
IPQ cause: heredity Correlation Coefficient 0.07 0.08 0.16*Sig. (2-tailed) 0.366 0.304 0.033N 169 170 170
Chapter 6 – Illness Appraisals in Psychosis 22
IPQ cause: chance Correlation Coefficient 0.06 0.08 0.15*Sig. (2-tailed) 0.415 0.319 0.046N 169 170 170
IPQ cause: personality Correlation Coefficient 0.01 0.28** 0.15*Sig. (2-tailed) 0.878 <0.001 0.049N 170 171 171
IPQ cause: stress Correlation Coefficient -0.05 <0.01 -0.06Sig. (2-tailed) 0.545 0.965 0.431N 170 171 171
IPQ cause: own behaviour Correlation Coefficient -0.07 0.13 0.01
Sig. (2-tailed) 0.374 0.088 0.894N 170 171 171
IPQ cause: others Correlation Coefficient 0.17* 0.12 0.19*Sig. (2-tailed) 0.028 0.131 0.016N 168 169 169
IPQ cause: poor medical care Correlation Coefficient 0.07 -0.02 0.16*
Sig. (2-tailed) 0.372 0.818 0.037N 170 171 171
IPQ cause: state of mind Correlation Coefficient 0.07 0.20** 0.14
Sig. (2-tailed) 0.346 0.009 0.060N 169 170 170
** Correlation is significant at the 0.01 level (2-tailed).* Correlation is significant at the 0.05 level (2-tailed).
6.6 DISCUSSION
6.6.1 What are the rates of anxiety, depression and self-esteem?
In this sample of people with a mean duration of illness of over 14 years, the mean
scores on the measures of anxiety and depression suggest mild comorbid anxiety and
depression. Using the cut-off suggested by Birchwood and colleagues of 15 points or
above (Birchwood and colleagues, 1993, 1997, 1998, 2000) for depression, 48%
suffer with depression. Applying this criterion to anxiety identifies 39% as suffering
from anxiety. The rate of depression is comparable to that of Birchwood and
Chadwick (1997) who found 53% to suffer from depression according to their
criterion, and van der Gaag et al. (2003) who report depression in 55%. The mean
score on the BDI of 16.5 in this population are slightly lower than in the Birchwood
and Chadwick 1997 study, although higher than the Birchwood and colleagues’ 1993
and 1998 studies.
Chapter 6 – Illness Appraisals in Psychosis 23
Both anxiety and depression scores are lower in this population than those of those of
Freeman et al. (1998) and Freeman and Garety (1999), although Barrowclough et al.
(2003), report their sample of 59 people with similar diagnoses to have an identical
mean BDI score of xx.
The self-esteem mean scores in this population of 114 are just over one standard
deviation lower than the normal mean of 140. This is half to one standard deviation
higher than self-esteem scores measured with the Robson SCQ reported by Freeman
et al. (1998) and the initial assessment scores of Hall and Tarrier (2003).
This population appears therefore to be suffering with mild to moderate depression
and anxiety and lower than normal self-esteem. Given the population consisted
mainly of outpatients known to mental health teams, principally people who were
considered amenable to be approached to talk about their mental health difficulties, it
is understandable that the group were not as distressed as samples in acute episodes
of symptomatic presentation or who had chronic persistent positive symptoms.
Nevertheless, the rates of significant clinical distress were considerable. The fact that
48% were classified as suffering from depression is consistent with the findings of
high-rates of co-morbidity of depression in people with schizophrenia or
schizophrenia-related disorders. While fewer people suffered with anxiety, and the
mean scores on the BAI were lower than that of depression, it was still a considerable
problem for some, with a range of anxiety scores of 0-53 and 25% scoring above 20.
The distress scores correlated highly with one another, particularly that of self-esteem
and depression which is to be expected given that a negative attitude towards the self
is a central to depression (Robson, 1988).
6.6.2 How do people with psychosis view their illness?
Responses to the Cause Scale of the IPQ, shows that people did not attribute their
mental health problems to environmental causes. Instead, high rates of endorsement
were found for the role of stress and state of mind, with over 70% in agreement. This
suggests good understanding of their illness. In addition, personality and others were
endorsed by a small majority of people. This is slightly contradictory but suggests
that people rated a number of factors as having caused their difficulties, consistent
with multi-factorial models of the onset of psychosis (e.g. Garety et al. 2001). Of
Chapter 6 – Illness Appraisals in Psychosis 24
interest, but difficult to interpret, is the finding that a sizeable minority (22.7%) rated
their problems as having been caused by poor medical care.
The pattern of endorsement described is very similar to the responses reported by a
sample of people with depression reported by Moss-Morris and Petrie (1996, reported
in Moss-Morris, 1997) who also found stress to be the most endorsed cause, followed
by the concepts relating to the self such as metal attitude and emotional state. In this
study, “the self” would include state of mind and personality which were endorsed by
73% and 59% of people and were the most endorsed after stress.
High percentages of the sample endorsed the presence of positive symptoms
(Identity), suggesting good awareness of their illness and willingness to report. This
is consistent with a recent report by Liraud et al. (2004) who found people with
psychosis to be accurate in their self-report of psychological symptoms. The least
endorsed symptom was that of visual hallucinations, with is consistent with rates of
visual hallucinations reported in the clinical literature (15-30%; Sartorius et al.,
1986).
All the subscales of the IPQ were correlated with one another. The strongest
correlation was found between negative consequences of illness and perceived long
duration. Interestingly, this was independent of actual duration of illness as no
association was found between actual duration of illness and any of the subscales of
the IPQ. The weakest, although significant, correlation was found between less
perceived cure/control over illness and negative consequences. Identity, or frequency
of psychotic symptoms correlated at a similar level with all three scales. These
patterns of relationship are consistent with the literature from physical illness studies,
with Hagger and Orbell (2003) also finding in their meta-analysis of 45 studies the
strongest correlation to be between the consequences and timeline scales. All
correlation coefficients in this study are larger than the mean correlation coefficients
corrected for measurement error reported by Hagger and Orbell.
With regard to the relationship between the cause items and other IPQ subscales, no
significant correlations were found between the Cure/Control subscale and any of the
cause items. Consequences showed a negative correlation with diet, such that
appraisal of illness as having been caused by diet was associated with less severe
negative consequences of illness. Greater negative consequences were perceived by
Chapter 6 – Illness Appraisals in Psychosis 25
people who saw their illness as being caused by their personality, stress, their state of
mind and others. Interestingly, longer Timeline was perceived by people who
perceived a hereditary cause of their illness. Longer Timeline also showed an
association with “others”, while Identity showed associations with own behaviour,
personality and state of mind.
It would appear that these findings raise the possibility of locus of control playing a
part in people’s appraisal, in that if one perceives the cause to be external (others or
heredity) the timeline is perceived to be longer. Others as a cause of illness (i.e. an
external cause) was also associated with greater negative consequences. In contrast,
greater frequency of symptoms (Identity) and negative consequences are largely
associated with causes originating from the self, although the locus of control of
stress is debatable. It is difficult to argue this with any degree of strength, however,
as locus of control was not assessed, and the analyses are correlational and do not
imply cause. In addition, it should be borne in mind that while significant, some of
these correlations are quite small, and they have not been corrected for multiple
testing. It could be, therefore, that some of the significant correlations are due to
chance.
All three PBIQ scales were significantly positively correlated with one another
indicating that negative views of illness (greater personal blame for the cause, lesser
degree of control and poor self-efficacy) are consistent across dimensions of illness.
Scores on the Loss subscale (including questions about poor work functioning and
self-efficacy) correlated with greater duration of illness, suggesting that aspects of an
individual’s illness history feed into their appraisal of illness.
6.6.3 How do the illness appraisal measures relate to each other?
Interestingly, the four IPQ scales (not including the individual Cause items) and the
PBIQ scales showed significant correlations with one another, suggesting a degree of
association between the scales. The highest correlation was found between IPQ
Cure/Control and PBIQ Entrapment of r=0.49. As Entrapment used to be titled
“Control” it appears these subscales are tapping similar constructs. However, in spite
of further correlations over 0.40 between PBIQ Entrapment and IPQ Identity and
PBIQ Loss and IPQ Cure/Control, the rest of the correlations are in the range of 0.25-
Chapter 6 – Illness Appraisals in Psychosis 26
0.37, suggesting that the measures are associated with one another but not measuring
exactly the same concepts. In addition, there is no particular pattern of correlations
which you would expect if there was a congruence between the measures, suggesting
that while the scales are associated with one another, there is nothing to support that
any of the scales are directly comparable to each other.
With regard to the pattern of association between the PBIQ scales and the IPQ Cause
scale, a number of the items showed significant correlations with each other, all with
small effect sizes. It is difficult to interpret anything meaningful from these results
with no obvious patterns. None of the PBIQ scales shows the same pattern of results
as the IPQ scales, with a slightly lower range of correlation coefficients (0.15-0.28
versus 0.17-0.32.
6.6.4 Summary
The group selected for inclusion in this study were a group of 172 individuals with a
long history of illness (over 14 years). They were found to describe causes of their
illness broadly consistent with psychological models of psychosis, and reported high
levels of positive symptoms. They were similar to many cross-sectional samples in
terms of their age at time of questionnaire completion and gender ratio (e.g. Freeman
et al., 1998, Birchwood and Chadwick, 1997). They were less distressed than some
samples (e.g. Freeman et al. 1998), but more distressed than others (e.g. Birchwood et
al., 1993). A high percentage of the sample suffered from anxiety, depression and
low-self-esteem which is significant given the relatively stable but chronic
population.
The illness perception measures showed significant correlations with each other and
in the case of the IPQ these were consistent with the wider literature with a physical
illness with regard to their direction and effect sizes.
Some association was found between the two illness perception measures, but with
the exception of PBIQ Entrapment and IPQ Cure/Control, only moderate effect sizes
were shown, suggesting the measures are related but the concepts are not identical.
Chapter 6 – Illness Appraisals in Psychosis 27
6.6.5 Conclusions
Chapter 6 – Illness Appraisals in Psychosis 28