Aberdeen Centre for Trauma Research, Royal Cornhill Hospital, Aberdeen, UK
Correspondence: Dr Alastair Hull, Lecturer in Mental Health, Aberdeen Centre for Trauma Research, Bennachie Building, Royal Cornhill Hospital, Cornhill Road, Aberdeen AB25 2ZH, UK
Funding from the Chief Scientist Office of the Scottish Home and Health Office.
See editorial, pp.
366368, this issue.
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ABSTRACT |
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Aims To examine the role of factors relating to the trauma, the survivors and the survivors' circumstances.
Method Ten years after the disaster, 78% (46/59) of the survivors were located, of whom 72% (33/46) agreed to be interviewed. A further three individuals completed postal measures.
Results The most stringent diagnostic criteria for post-traumatic stress disorder (PTSD) were met by 21% (7/33) of the survivors over 10 years after the disaster. Features such as physical injury, personal experience and survivor guilt were associated with significantly higher levels of post-traumatic symptoms.
Conclusions A narrow definition of factors affecting outcome will limit the potential for improving survivor well-being in the long-term after major disasters. Specific symptoms that are not included in the criteria for the diagnosis of PTSD, together with issues such as re-employment, need to be addressed.
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INTRODUCTION |
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The Piper Alpha oil platform disaster took place on 6 July 1988, resulting in the deaths of 167 men and leaving 59 survivors. It involved the complete destruction above sea level of the platform at 193 km northeast of Aberdeen, a city in the Grampian region of Scotland. The crew were exposed to a range of extreme stressors, for example: toxic fumes, fire, being trapped, extended threat to life either on the platform or in the sea, witness to the injury to and/or the death of others, traumatic bereavement, and delayed rescue and medical care. Further details are available elsewhere (Alexander, 1991, 1993).
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METHOD |
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Disaster research has in the past compared survivors with a control group who have not experienced the traumatic event. This will only produce information about specific aspects of the event if the experimental and control groups vary in just one dimension (Holen, 1993). It was not possible to generate such a control group for this study.
Assessments
Semi-structured interview
This was divided into sections and collected information on a number of
areas, including: sociodemographics; concurrent stresses; detailed and
specific questions about aspects of the subjects' personal experience of the
disaster; physical problems and their care; post-traumatic psychosocial
problems and their management; and employment problems. Physical injuries were
further investigated by case-note review.
Self-report outcome measures
The Impact of Event Scale Revised (IESR;
Marmer & Weiss, 1997) is a
widely used, valid and reliable 22-item scale measuring subjective distress
caused by intrusion (e.g. flashbacks and nightmares), avoidance and
hyperarousal. It provides a total score (range 0-88).
The Post-Traumatic Symptom Scale (PTSS12; Holen, 1993) is a 12-item scale validated on a similar post-disaster population (the survivors of the Alexander L. Keilland oil platform disaster), and is designed to measure certain post-traumatic phenomena (e.g. irritability and impaired concentration).
The General Health Questionnaire 28 (GHQ28;
Goldberg & Hillier, 1979)
is a 28-item research version of the GHQ that provides a measure of general
psychopathology. Using the conventional binary GHQ scoring method (range
0-28), we defined a total GHQ score 4 as indicative of psychiatric
caseness (i.e. if a clinical interview were undertaken a psychiatric
diagnosis would be highly likely). For some analyses the total score was used
as a continuous variable.
The Hopelessness Scale (Beck et al, 1974) is a 20-item, well-established scale that provides a subjective measure of hopelessness with a total score (range 0-20).
Diagnostic interview
The Clinician Administered Post-Traumatic Stress Disorder (PTSD) Scale for
DSMIV, Current and Lifetime Diagnostic Version (CAPSDX;
Blake et al, 1995) is
a highly structured interview. It measures the frequency and intensity of the
17 DSMIV (American Psychiatric
Association, 1994) symptoms of PTSD (each scored 0-4), five
associated features (each scored 0-4), social and work impact, global
improvement, and severity (each scored 0-4). Both acute and current symptoms
were assessed. For the purposes of this study we used the most stringent
empirically derived scoring rule (Weathers
et al, 1999) to convert the continuous severity scores
into dichotomous categories for the analyses of the data. This rule,
F1/12/SEV65 (i.e. a significant level of PTSD symptom severity and a
distribution of symptoms corresponding to DSMIV diagnostic criteria),
was chosen to confirm an unequivocal diagnosis of PTSD in view of the
relatively small number of survivors, to avoid false positives. This PTSD
diagnosis and the total CAPS-DX scores were used in the analyses.
Procedure
Subjects were interviewed by a clinician experienced in the diagnosis and
assessment of PTSD (A.M.H.), using the specially designed semi-structured
interview and the CAPSDX. The four self-report questionnaires were also
administered at the time of the interview.
Statistical analysis
SPSS for Windows, version 9 (SPSS Inc, Chicago, IL) software was used to
input and to analyse the data. Non-parametric methods were needed owing to
skewed distributions and heterogeneity of variance. The MannWhitney
U-test (corrected for ties) assisted between-group comparisons.
Differences for paired data were analysed by means of the Wilcoxon matched
pairs signed rank test. The relationship between variables was assessed by
means of Spearman's rank correlation coefficient, the McNemar test for matched
samples, and the -squared test for association, including Fisher's exact
test when expected values were less than 5. All probability values relating to
the hypotheses were one-tailed. Because of the risks of multiple comparisons
generating spurious findings, only those with a probability value of 1% or
less were considered significant. The results of all other data analyses are
available upon request from the authors.
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RESULTS |
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Prevalence of PTSD and other psychological symptoms
As measured using the scoring rule F1/12/SEV65, 21% (7/33) had a current
diagnosis of PTSD and 73% (24/33) had a diagnosis of PTSD using this same rule
for symptoms reported in the first 3 months after the disaster. In addition,
survivors with sustained anger, as measured on the CAPSDX, had
significantly higher current post-traumatic symptoms on the PTSS-12 scale
(z=-2.949; P=0.01) and diagnostic interview (z=-2.636;
P=0.01). Survivors had median IESR and PTSS12 scores of
19 (range 0-60) and 6 (range 0-12), respectively.
Current GHQ28 caseness was 44% (16/36). As measured by the semi-structured interview, 76% (25/33) of the survivors stated that they had experienced psychological problems within 1 month, with symptoms starting within 3 months in 97% (32/33). In addition, 64% (23/36) stated that some of their psychological problems were still present. Survivors had a median Hopelessness Scale score of 4, with a range of 0-15.
More than one-third (36%; 12/33) of survivors described survivor guilt (I should not have survived) after 10 years, and 70% (23/33) reported acute guilt. Survivors who experienced acute survivor guilt were significantly more likely to have severe acute PTSD, as measured by CAPSDX (Fisher's exact test, P=0.001). Similar findings were evident for performance guilt (I should have done better); 33% (11/33) had performance guilt currently and 61% (20/33) had the symptom acutely. Survivors with acute performance guilt were significantly more likely to have severe acute PTSD (Fisher's exact test, P=0.01), and those with sustained performance guilt had significantly higher rates of PTSD on the CAPSDX (Fisher's exact test, P=0.01). McNemar tests on survivor and performance guilt each had a significance level of P=0.01, indicating that symptom severity and occurrence decreased over time. Survivors who reported chronic dissociative symptoms were significantly more likely to have post-traumatic symptoms on the PTSS-12 (z= -2.77, P=0.01) and on the CAPSDX (Fisher's exact test, P=0.01), and to have higher Hopelessness Scale scores (z= -2.9, P=0.01).
Personal experience
The majority of survivors (97%; 35/36) experienced the loss of a friend;
86% (31/36) thought they might die; 86% (31/36) saw someone who had been
seriously injured or killed; and 58% (21/36) saw someone being killed or
injured. Survivors who saw the death of and/or injury to colleagues had
significantly higher IESR scores (z= -2.47, P=0.01) and higher
total CAPSDX scores (z= -2.88, P=0.01). There were no
significant associations between delayed rescue and general or specific
post-traumatic symptomatology.
Physical injury
The majority of participants were physically injured (83%; 30/36), with 56%
(20/36) sustaining more than one injury and 42% (15/36) requiring hospital
admission. Survivors who jumped from the platform were significantly more
likely to have burns (2=7.67, d.f.=1, P=0.01), as
were those who spent longer periods in the water (
2=6.52,
d.f.=1, P=0.01). Survivors who sustained fractures during the
disaster had significantly higher post-traumatic symptom scores on the
IESR scale (z= -2.781, P=0.01). No other statistically
significant association was found between the nature and/or extent of physical
injury and the prevalence or severity of PTSD.
Social and occupational functioning
The majority of survivors (78%; 28/36) reported difficulties finding work
post-trauma; these survivors were significantly more likely to report higher
post-traumatic symptom scores on the IESR (z= -3.065; P=0.001)
and had significantly more severe acute PTSD symptoms at diagnostic interview
(2=8.80, d.f.=1, P=0.01). Survivors meeting
diagnostic criteria for PTSD, both acutely and currently (as measured by
CAPSDX), had significantly greater impairment in social and
occupational functioning (z= -3.61, P=0.001).
Stressors
The prevalence of pre-trauma stressors was generally low, the most common
being marital disharmony (42%, 14/33), employment difficulties (27%, 9/33) and
bereavement (27%, 9/33). Participants with accommodation problems before the
disaster were significantly more likely to meet GHQ-28 caseness (Fisher's
exact test, P=0.01). Survivors with a pre-trauma history of physical
illness in a family member had significantly higher IESR scores (z=
-2.539; P=0.01), but no other stressor was significantly related to
any outcome measure either singly or combined. McNemar tests on all areas of
concurrent life stresses indicated that for each variable the extent of the
problem increased after the disaster (P=0.01). The effects of
traumatic events that occurred either before or after the disaster could not
be tested statistically as only 2 subjects had experienced another traumatic
event. Survivors meeting GHQ caseness currently (10 years post-trauma) were
significantly more likely to have developed alcohol problems (Fisher's exact
test, P=0.01) or financial problems (Fisher's exact test,
P=0.01) after the disaster.
Treatment and support systems
Psychological problems were reported by 97% (32/33) of survivors, with 76%
(25/33) subsequently having individual therapy; 55% (18/33) prescribed
medication; 21% (7/33) group psychotherapy; and 55% (18/33) a combination of
treatments (Table 2). Having
treatment was associated with having a diagnosis of acute PTSD (Fisher's exact
test, P=0.01). The ease of access to treatment varied considerably
for group psychotherapy, but both individual therapy and medication were
readily available to the majority of those who used them. A support group in
Aberdeen and the helpline were both viewed as helpful by the large majority of
participants who used them (Table
2). A reunion held 12 months after the disaster was viewed as
helpful by most who attended it (Table
2).
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Worst long-term effects
The majority of survivors (61%, 22/36) stated that the worst long-term
effect of the disaster was its impact on their emotional and psychological
well-being and on their relationships. Only 8% (3/36) stated that situational
problems (e.g. financial difficulties) were the worst long-term effects of the
disaster.
Positive aspects
Of survivors interviewed, 61% (22/36) stated that some good had come of the
experience, with 44% (16/36) identifying changes in emotional and personal
life (e.g. closer to family, more emotionally expressive), and 17% (6/36)
specifying situational changes (e.g. financial security through compensation)
as the main positive effects.
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DISCUSSION |
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A major issue in trauma research is the validity of symptom reporting and the accuracy of recall of traumatic events. Are the survivors the best source of accurate information about the stressor? Their psychological adjustment may colour their recall of events, and the accuracy of recall of traumatic events has been found to decay over time (McFarlane, 1988). However, corroboration was available for a large proportion of the accounts of the individual survivors' personal experience from other survivors, with reassuring consistency. Furthermore, data about the Piper Alpha disaster were collected soon after the event in both clinical settings and the legal inquiry. In trauma research, particularly in long-term follow-up studies, this is unusual.
Traumatic events also affect social and occupational functioning adversely. The high levels of post-traumatic reactions found in this group only partially relate to features of the stressor itself, such as physical injury and witnessing injury or death, or its aftermath. A complex interrelationship exists between features of the trauma, the characteristics of the survivor (e.g. sustained guilt or anger) and the survivor's circumstances (e.g. lack of support or perceived lack of control).
Guilt would appear to be one of the central and most chronic symptoms of PTSD. Green (1993a) has stated that guilt is infrequent and, if ranked, would have tied for last place among the PTSD symptoms of survivors after the Buffalo Creek flood. In our study, performance and survivor guilt were found to be not only persistent and severe symptoms but strongly associated with severe acute PTSD and enduring PTSD. Van der Kolk (1996) and others have suggested that exposure therapy (facing the feared situation or traumatic memory either in vivo or in fantasy) in the presence of guilt may worsen both shame and guilt. This may explain the adverse effects of exposure found by Pitman et al (1991). The presence of guilt must be identified before the use of exposure therapy, to prevent the exposure itself having a psychonoxious effect. Early guilt will both encourage, and be further exacerbated by, a negative appraisal of the traumatic event. The identification and treatment of guilt would appear to be important in facilitating the survivor's ability to recover. Furthermore, the importance of the recognition of guilt is highlighted by research demonstrating that guilt is the most significant explanatory factor in suicidal behaviour in combat veterans with PTSD (Hendin & Haas, 1991). Non-trauma specialists may not enquire about guilt as it is not classified as one of the central symptoms of PTSD; concentrating solely on the core criteria for the diagnosis of PTSD will give a restricted view of the impact of the trauma and of the necessary management for the victim of the traumatic event. Guilt and dissociative symptoms are currently termed associated symptoms of PTSD rather than core criteria, but our study would suggest that both are strongly associated with the development of both acute and chronic PTSD.
Personal experience
Threat to life has been shown to be a significant predictor of long-term
outcome (Green,
1993b) but threat to life was so prevalent in our study
(86%) that analysis was not possible. Exposure to the grotesque, such as
seeing the death of, or injury to, another person, has been shown elsewhere to
be highly disturbing (Green,
1993b). Traumatic bereavement, particularly if the person
is present at the time of the death, is predictive of PTSD across a wide
variety of events (Green,
1993b). The vast majority (97%) of Piper Alpha survivors
experienced such loss, often of large numbers of close workmates and friends.
Physical injury is seldom examined in research on traumatic events despite its
relationship to threat to life. Our study shows the association of physical
injury with PTSD and hopelessness, and thus emphasises the need for close
liaison between surgeons and physicians, and their mental health
colleagues.
The traumatic event was not universally and equally stressful for all survivors. Researchers must examine the specific aspects of such individual's experience rather than overgeneralising about the effects of traumatic events (Holen, 1993). Any disaster may have unusual characteristics, and the evaluation of the characteristics of the stressor is essential to allow the application of the findings to other trauma populations.
Social and occupational functioning
Re-employment difficulties for survivors were significantly associated with
poorer outcome. Survivors acknowledged many diverse reasons for employment
problems beyond their psychological and physical injuries, such as
experiencing prejudice in the workplace as a result of being a survivor of the
Piper Alpha disaster. The ability to adjust to working offshore again was
related to better outcome: a large proportion of the survivors (33%; 12/36)
had worked offshore again despite the extent of the disaster and the rates of
physical injury. For some this was only for a brief period, but others
returned to offshore work within weeks and continued in similar jobs. This
might have been the result of a lack of other marketable skills, of the need
as reported by survivors to get back on the horse or a
re-enactment of the trauma (Van der Kolk,
1989). Survivors reported a restriction of social interaction and
lessening of interest in their previous leisure pursuits after the disaster,
which persisted for many survivors for more than 10 years.
Treatment and support systems
A coordinated and flexible response to major disasters is critical. It was
reassuring to find that survivors of Piper Alpha were both aware of the need
for treatment and were able to access it where they lived. Over 81% (29/36)
received at least one form of treatment and many (69%; 25/36) also made use of
the support system (e.g. the support group and the helpline) and other
non-professional help (82%; 27/33). The helpline and the support group were
found to be helpful by the large majority of survivors who used them. The one
complaint regarding the support group was its distance from some of the
survivors who lived geographically far from Aberdeen, some outside Britain.
Some of the survivors living further from the centre of interest and support
reported feeling isolated, although some had actively sought isolation from
other survivors and from the media coverage.
The men had a varied experience of professional treatment, with approximately three-quarters (76%) having individual therapy and over half having a combination of treatments. Survivors who made use of treatment for psychological symptoms were those who reported severe acute post-traumatic symptoms. The survivors' symptoms and level of functioning had improved over the 10-year period, with fewer individuals having specific symptoms such as survivor and performance guilt and fewer meeting PTSD diagnostic criteria. These findings are similar to research by others such as Kessler et al (1995), who found a shorter duration of symptoms (3 years) among those who obtained professional help than among those who did not (5 years).
Strengths and limitations of the study
A strength of our study is that we examined an unselected survivor
population; all survivors were invited to participate. The participation rate
was high, with 78% of survivors who could be traced agreeing to take part.
Research elsewhere, most notably by Weisæth
(1989), has shown that
resistance to initial interview and examination was related to severity of
exposure and to the presence of post-traumatic stress reactions. Weisæth
has argued that the true prevalence of PTSD would be underestimated unless
response rates were high. The number of subjects in this study is small as a
result of the small number of survivors of the disaster; also, the survivors
may represent a sub-group of individuals who behaved in ways likely to
optimise their survival (Weisæth,
1984).
Trauma research is bedevilled by ethical and methodological constraints imposed upon researchers. Any approach needs careful planning, yet rarely is there sufficient time to devise elegant research strategies. In pursuit of information there is the perennial risk of re-traumatising survivors by exposing them to distressing recollections of their trauma at interview. To limit the potential for our contact to cause distress we were careful to avoid the anniversary of the disaster because, as highlighted by Ehlers & Clark (2000), symptom-reporting rises at such a time. In addition, we gave participants the option of completing postal measures if they believed an interview might prove too distressing. Three survivors chose to participate in the study by this means. Some of the interviewed survivors did report an increase in intrusive symptoms both at the time of the interview and in the week preceding it. An assessment of the validity of responses is included in the CAPS-DX and was found to be high for the participants in this study. There was also a high rate of consistency between self-report measures and diagnostic interview. We are aware that the assessment of lifetime PTSD at the same time as the report of current symptoms may have led to a retrospective bias in symptom reporting.
There are several aspects relating to the data collected and reported that should be considered. The personal characteristics of the crew of the Piper Alpha are important in understanding their post-trauma reactions. The crew of the Piper Alpha platform were all male, a self-selected group (unlike transportation disaster victims), accustomed to both the onshore/offshore pattern of work and to spending long periods of time with close workmates. The crew can be considered to have been screened for some of the vulnerability factors for psychological illness, such as preexisting physical illness, which may account for the low levels of concurrent stressors the survivors reported at the time of the disaster. The work pattern might also have encouraged the development of other vulnerability factors such as alcohol misuse (Ruch & Leon, 1983) but this was not evident from self-reports in this study; only three men stated that they had had alcohol problems before the disaster. We acknowledge that the absence of corroboration of the subjects' alcohol intake might have led to an underestimation of the prevalence of alcohol problems.
Although survivors of the Piper Alpha disaster experienced high levels of general and specific post-trauma psychosocial morbidity, the majority (61%; 20/33) identified something positive to have come from the tragedy, whether personal or situational. This would not be consistent with the cognitive model proposed by Ehlers & Clark (2000), which proposes that individuals with persistent PTSD are unable to see the trauma as a time-limited event that does not have global implications for their future. Clearly this is an issue to be clarified by further empirical research. In general the participants were of the opinion that lessons learned from large-scale disasters resulted in improved response to traumatic events and treatment techniques for survivors; it is to be hoped that this is in fact the case. Professionals must also be alert to factors that might be modified to improve the short-term and long-term outcome for survivors of traumatic events.
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Clinical Implications and Limitations |
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LIMITATIONS
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ACKNOWLEDGMENTS |
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Received for publication January 2, 2002. Revision received June 13, 2002. Accepted for publication June 14, 2002.
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