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PTSD, Acute Stress, Performance and
Decision-Making in Emergency Service
Workers
Cheryl Regehr, PhD, and Vicki R. LeBlanc, PhD
Despite research identifying high levels of stress and traumatic stress symptoms among those in the emergency
services, the impact of these symptoms on performance and hence public safety remains uncertain. This review
paper discusses a program of research that has examined the effects of prior critical incident exposure, acute
stress, and current post-traumatic symptoms on the performance and decision-making during an acutely stressful
event among police officers, police communicators, paramedics and child protection workers. Four studies, using
simulation methods involving video simulators, human-patient simulators, and/or standardized patients, examined
the performance of emergency workers in typical workplace situations related to their individual profession.
Results varied according to level of acuity of stress and the nature of performance and decision-making. There was
no evidence that PTSD had a direct impact on global performance on tasks for which emergency responders are
highly trained. However, PTSD was associated with assessment of risk in situations that required professional
judgement. Further, individuals experiencing PTSD symptoms reported higher levels of acute stress when faced
with high acuity situations. Acute stress in these studies was associated with performance deficits on complex
cognitive tasks, verbal memory impairment and heightened assessment of risk.
J Am Acad Psychiatry Law 45:184 –92, 2017
Society relies on professionals in emergency service oc-
cupations to make sound judgements and perform ef-
fectively in response to highly stressful, life-threatening
events. Yet, as a result of working in such environ-
ments, individuals in the emergency services are
prone to high rates of stress-related problems
1
in-
cluding posttraumatic stress disorder.
2
Studies of
paramedics report trauma symptoms in a range con-
sistent with PTSD in 20 to 30 percent of respon-
dents.
3–5
A study of police communicators found
that 31 percent reported symptoms at a level consis-
tent with a diagnosis of PTSD.
6
Child protection
workers, charged with assessing children at risk of
abuse, report high levels of posttraumatic symptoms
related not only to exposure to the trauma of others,
but also to threats and assaults against themselves.
7
Following a critical event such as a police shooting of
a civilian, trauma symptoms in the high or severe
range can affect as many as 46 percent of the officers
involved.
8
This association between emergency service work
and posttraumatic stress has been recognized by or-
ganizations providing disability insurance to workers
such as the U.S. Federal Employees’ Compensation
Act (FECA).
9
More explicitly, Section 24.2
2
of the
Alberta (Canada) Workers’ Compensation Act that
came into effect in December 2012 provides that:
If a worker who is or has been an emergency medical tech-
nician, firefighter, peace officer or police officer is diag-
nosed with post-traumatic stress disorder by a physician or
psychologist, the post-traumatic stress disorder shall be pre-
sumed, unless the contrary is proven, to be an injury that
arose out of and occurred during the course of the worker’s
employment in response to a traumatic event or series of
traumatic events to which the worker was exposed in car-
rying out the worker’s duties [10].
This approach suggests an underlying assumption
that PTSD, impairment of functioning, and disabil-
ity are linked. To this end, psychiatrists and other
mental health professionals are frequently called
Dr. Regehr is Professor, Factor-Inwentash Faculty of Social Work,
Faculty of Law and the Institute for Medical Sciences at the University
of Toronto, Ontario, Canada. Dr. LeBlanc is Associate Professor and
Chair of the Department of Innovation in Medical Education, Uni-
versity of Ottawa, Ontario, Canada. Presented at the 43rd Ameri-
can Academy of Psychiatry and the Law Annual Meeting, Mon-
treal, Que´bec, Canada, October 25–28, 2012, and at the 17th
Canadian Academy of Psychiatry and Law Annual Meeting, Whis-
tler, British Columbia, Canada, March 4 –7, 2012. Address correspon-
dence to: Cheryl Regehr, PhD, Faculty of Law, University of Toronto,
27 King’s College Circle, Toronto, Canada, M5S 1A1. E-mail:
cheryl.regehr@utoronto.ca.
Disclosures of financial or other potential conflicts of interest: None.
184 The Journal of the American Academy of Psychiatry and the Law
SPECIAL SECTION: STRESS AND TRAUMA
upon to make judgements about whether the distress
that is experienced by an individual following an
event meets the criteria for PTSD, and subsequently
the degree to which these symptoms impair func-
tioning. In the first instance, concerns have been
raised regarding the readiness of clinicians to diag-
nose PTSD in high-risk occupations without con-
ducting comprehensive assessments.
11,12
Second, al-
though the AAPL Practice Guidelines on Forensic
Evaluation of Psychiatric Disability
13
require that a
clinician correlate the requirements of the job with
the claimed impairments,
14
limited empirical data
are available to support judgements in this area.
Perhaps in part due to confounds of comorbid
psychiatric disorders
15
and motivational factors such
as the fear of losing disability benefits, that may con-
tribute to exaggeration of symptoms,
16
research on
the specific deficits that are attributable to PTSD has
been somewhat contradictory.
17
PTSD has been as-
sociated with mild impairments in memory, atten-
tion, and learning in individuals who are seeking
treatment and who manifest a high incidence of psy-
chiatric comorbidities.
14,18,19
However, researchers
reported an absence of neuropsychological deficits
associated with PTSD and trauma exposure in non-
patient populations.
20
Furthermore, individuals
with PTSD largely perform within the normal range
of standardized tests of neuropsychological function-
ing, suggesting that, where deficits are present, they
are not at the level of clinical impairment.
15,21,22
To assess apparently contradictory research
findings, Brewin and colleagues
17
conducted a
meta-analysis and determined that there is a mild
to moderate association between memory impair-
ment related to emotionally neutral information and
PTSD in both civilian and military samples. This
relationship is stronger for verbal memory than for
visual memory. More recently, Horner and col-
leagues found that patients with PTSD have deficits
in attentional functioning compared with controls
on one measure of focused attention, digit span
memory, but not on all measures.
23
The findings
suggest that attentional impairment in people with
PTSD may be selective and that a more nuanced
approach to assessing the impact of PTSD on perfor-
mance is needed.
Acute stress has also been associated with altered
perceptions and impaired performance. Given the
nature of the work environment encountered by
emergency service occupations, situationally pro-
voked acute stress must be considered in tandem
with PTSD. Both state and trait anxiety, even when
mild, are associated with an increased likelihood of
interpreting ambiguous stimuli, such as facial expres-
sions, as threatening.
24
Anxious individuals have an
attentional bias toward threat stimuli, assessing the
risks in a particular situation as being higher than do
individuals in neutral or positive moods and re-
sponding faster to a threat.
25,26
In this way, risk ap-
praisal influences judgment regarding the likelihood
of future events (i.e., that the risk will lead to a neg-
ative outcome)
27
and subsequently guides the behav-
ior of the individual. For instance, police officers
experiencing anxiety are more easily distracted by
task-irrelevant threat-related information and show a
response bias toward shooting.
28
Other research con-
sistently notes that anxious individuals are more risk
averse.
27
Further, anxious individuals demonstrate
impairments in verbal reasoning, especially in per-
forming high-demand tasks, when compared with
individuals with low levels of anxiety.
27
Research on
biological correlates of emotional anxiety supports
this finding. For instance, acute cortisol elevations
have been associated with impairments in verbal, so-
cial, and declarative memory and in selective atten-
tion.
29,30
Increased cortisol production is most likely
to occur when stressors are uncontrollable, ambigu-
ous, novel, of long duration, or contain an element of
psychosocial evaluation.
31
This finding has impor-
tant implications when considering the impact of
PTSD on performance in emergency-response
professionals.
In this review, we present a program of research
that has examined the effects of prior critical incident
exposure, acute stress, and current posttraumatic
symptoms on performance and decision-making
during an acutely stressful event among police offi-
cers, police communicators, paramedics, and child
protection workers.
Studies
In each of four studies, participants completed a
series of questionnaires before participating in a sim-
ulated stressful scenario. Demographic information
was obtained through short questionnaires that as-
sessed age, gender, and years of service. Trauma ex-
posure in the workplace was assessed in two studies
(child protection and police communicators) using a
specifically designed instrument. In a third study,
Regehr and LeBlanc
185Volume 45, Number 2, 2017
with police recruits, the Critical Incident History
Questionnaire (CIHQ)
32
was used to assess police
duty-related trauma history by measuring the fre-
quency of exposure to each of 34 critical incidents
(e.g., being shot at).
Traumatic stress symptoms were elicited by the
Impact of Event Scale-Revised (IES–R),
33
which as-
sesses posttraumatic stress symptoms for any specific
life event. It extracts dimensions that parallel the de-
fining characteristics of the DSM-IV criteria for
PTSD,
34
which are signs and symptoms of intrusive
cognitions and affects, together or oscillating with
periods of avoidance, denial, or blocking of thoughts
and images. This scale is reported to have high inter-
nal consistency with a Cronbach
␣
of .86 and a test–
retest reliability of .87.
33
The stress responses of the workers were assessed
with a subjective anxiety measure (the State-Trait
Anxiety Inventory; STAI) and a physiological mea-
sure (salivary cortisol). Baseline measurements were
taken at the start of the study sessions, and response
measures were obtained at specific times after each
simulation. The STAI is a commonly used assess-
ment for stress manipulations, as it has been shown
to be sensitive to acute stress manipulations.
35
The
state anxiety (S-anxiety) scale consists of 20 state-
ments (e.g., “I am tense”), to which respondents in-
dicate their level of agreement on a 4-point scale
regarding how they feel at the given moment (1, not
at all; 2, somewhat; 3, moderately so; and 4, very
much so). The internal consistency of the STAI
S-anxiety scale is high, with an
␣
of .92.
Salivary Cortisol
Activation of the hypothalamic–pituitary adrenal
axis, which occurs during acute stress responses, was
measured by determining salivary cortisol levels. Sal-
ivary cortisol levels are closely associated with plasma
cortisol levels,
36
yet are collected in a simple, nonin-
vasive manner.
37
Analyses of salivary cortisol were
conducted with an immunoassay technique.
38
Two
baseline measures were obtained in the introduction
phase (at 10 and 1 minute before each scenario), as
well as 20 and 30 minutes after the onset of each
event. To control for diurnal variations in baseline
cortisol levels, data collection occurred between the
hours of 11 a.m. and 5 p.m., when baseline cortisol
levels are stable.
Study 1: PTSD, Acute Stress, and
Performance in Police Recruits
In the first study,
39
police recruits participated in a
scenario utilizing a FATS (Firearms Training Sys-
tems) simulator. FATS simulation involves the pro-
jection of a realistic situation onto a blank screen in a
specially designed simulation room. The simulation
is programmed to respond to the police recruits’ ac-
tions (i.e., communications, chemical spray, and fire-
arms). The scenario constructed for this research in-
volved a 911 call to respond to a domestic dispute in
which the officer’s entry is first barred by an aggres-
sive male, who subsequently allows the officer into
the home and down a blind hallway. Upon entry to a
room at the end of the hallway, an unresponsive fe-
male is discovered lying on the floor, and the officer
must determine the correct line of action. Possible
considerations involve the ongoing presence of the
perpetrator, the victim’s need for medical attention,
and the safety of the officer. Participants were video-
taped during the simulations for the purpose of later
evaluation. The videotaped performance of each par-
ticipant was assessed independently by three expert
raters at the Ontario Police College on two measures:
one measuring specific behavioral competencies in
the scenario and a second ranking performance
against peers.
Eighty-four police recruits enrolled in basic con-
stable training participated in the study. Participants
represented 14 different police services, 71.4 percent
were male, 45.8 percent were single, and the mean
age was 30.31 (SD 6.0). They had been with their
current police service for a mean of 9.16 weeks (SD
16.06). Twenty percent had worked in the emer-
gency services including policing, ambulance, fire,
and hospital or had been in the military.
Results
Of the 84 participants, 79.3 percent reported be-
ing exposed to at least one critical event, including
being seriously injured or beaten, being threatened
with a weapon, being present when another officer
was severely injured, receiving threats against loved
ones in retaliation for their police work, and seeing
someone die or discovering human remains. With
respect to trauma symptoms, 51 percent of the re-
cruits scored in the no-to-low trauma symptom
range, 16 percent scored in the moderate range, 14
percent scored in the high range, and 19 percent
scored in the severe range.
40
Cortisol levels were not
PTSD, Acute Stress and Performance
186 The Journal of the American Academy of Psychiatry and the Law
associated with symptoms of PTSD. However, in-
creases in subjective anxiety during the scenario cor-
related significantly with the IES-R avoidance sub-
scale (r⫽.273; pⱕ.01), the IES-R intrusion
subscale (r⫽.273; pⱕ.01), and the IES-R total
score (r⫽.265; pⱕ.01).
40
There was a wide range of performance within the
sample. Pearson correlation analyses revealed that the
recruits’ scores on the IES-R did not correlate with
their scores on the behavior competencies ratings
(r⫽.06; p⫽.63) or on the relative rankings of
performance (r⫽.08, p⫽.46). Similarly, degree of
exposure to critical events, as measured by scores on
the Critical Incident History Questionnaire, did not
correlate with the recruits’ scores on the behavior
ratings (r⫽.06; p⫽.60) or on the relative rankings
of performance (r⫽.11; p⫽.31).
39
Acute stress, as measured by the STAI, did not
correlate with performance at any time. Cortisol lev-
els 20 minutes after the event correlated significantly
with both the relative ranking of performance and
the performance checklist (r⫽.18, p⫽.05 and r⫽
.19, p⫽.04). Thus, although subjective distress was
not associated with performance, greater cortisol lev-
els were associated with better performance in this
study.
41
Study 2: PTSD, Acute Stress, and Risk
Assessment in Child Protection Workers
This study investigated the degree to which the
previous experiences of workers and their preexisting
emotional state interact with context variables en-
countered in a clinical situation, and whether these,
in turn, influence professional judgment regarding
the acute risk to a child.
42
The research design was a
prospective randomized controlled trial that utilized
standardized patients performing in scenarios con-
structed to depict typical child protection cases in a
2⫻2 factorial design. Two 15-minute scenarios to
simulate acutely stressful clinical encounters were de-
veloped and pilot tested with a cross-section of child
protection workers to ensure that they were compa-
rable with real client encounters. One scenario in-
volved an interview with a mother (fictitiously
named Ms. Smith) of an infant following a report by
the child’s daycare provider that welts had been ob-
served on the child. A second scenario involved an
interview with the mother (fictitiously named Ms.
Samuels) of a latency-aged child after a report by a
school that the child had reported physical abuse.
Each scenario was presented in one of two forms:
with a confrontational parent and with a noncon-
frontational parent. The order of interviews was
counterbalanced to allow for examination of various
order effects. Standardized patients (SPs) were used
to portray the role of parents. SPs are healthy indi-
viduals trained to portray the personal history, phys-
ical symptoms, emotional characteristics, and every-
day concerns of actual patients. At the end of each
scenario, participants completed risk assessment
measures; the Ontario Risk Assessment Measure
(ORAM) and the Ontario Safety Assessment (OSA)
(described in detail in Ref. 42). The workers were
familiar with both tools and used them as a standard
part of mandated practice.
Ninety-six child protection workers employed at
12 different child protection offices located in a large
urban center, smaller cities, and rural communities
participated in the study. The participants were
intake workers (48%), family services workers
(34.4%), or managers and supervisors (4.3%) or they
worked in other positions (13.5%) in the child pro-
tection agency.
Results
Eighty-five percent of respondents indicated that
they had been exposed to at least one critical incident
at work, including death of a child, death of an adult
client, and assaults and threats against themselves.
Scores on the Impact of Event Scale indicated that
a sizable minority of participants were currently
experiencing high levels of traumatic stress symp-
toms. Thirty individuals (32%) scored in the high or
severe range of the scale. Of these, 18 (19%) fell in
the range that is considered consistent with a clinical
picture of PTSD. These high rates of reported expo-
sure to critical events and traumatic stress symptoms
are consistent with previous research on child protec-
tion workers.
7
The number of critical events to
which workers reported being exposed was correlated
negatively with STAI scores at the end of the scenario
(r⫽⫺.390, p⬍.001). Scores on the IES-R corre-
lated positively with peak STAI scores (r⫽.309, p⬍
.001). That is, workers with less exposure to critical
events but with higher levels of traumatic symptom
scores experienced greater anxiety during the
simulations.
42
Analyses revealed that the number of critical inci-
dents reported by participants was negatively associ-
ated with the ORAM risk category (Spearman’s
Regehr and LeBlanc
187Volume 45, Number 2, 2017
Rho ⫽⫺.253, pⱕ.013) but was not significantly
associated with a finding of safe or unsafe on the OSA
(t⫽⫺1.785, pⱕ.077). That is, on the ORAM
assessment tool only, as the number of exposures to
critical events increased, workers were less likely to
determine that a child was at risk of abuse.
42
As workers had higher levels of symptoms of trau-
matic stress, they were less likely to determine that a
child was at risk of abuse or neglect on the OSA
(IES-R Total Score, t⫽4.116, pⱕ.001). STAI
scores immediately after the first interview (the peak
STAI score) were significantly associated with iden-
tifying that a child was at risk (t⫽2.003, pⱕ
.048).
42
Peak cortisol response was significantly as-
sociated with increased assessed risk on the ORAM
for the infant (r⫽.209; pⱕ.01) but not the older
child. Further, in the first scenario, when workers
reported greater subjective and physiological stress
responses, they rated the overall risk to the child as
being greater in the confrontational condition than
in the nonconfrontational condition (pⱕ.05). The
overall perceived risk to the child did not differ be-
tween the two conditions in the second scenario,
when the workers exhibited lower stress responses.
In summary, across the two scenarios, the state
anxiety was associated with greater rating of risk on
one of the assessment measures.
43
Peak cortisol levels
were associated with greater rating of risk for the
younger child only. Increased levels of posttraumatic
symptoms reduced the likelihood that a worker
would determine that a child was at risk.
42
Study 3: PTSD, Acute Stress, and
Performance in Paramedics
For the purpose of this study, a high-acuity event
was created with the use of a high-fidelity mannequin
placed in an ambulance simulator. The paramedics
were required to manage a cardiac patient complain-
ing of chest pain, in both a low-stress and a high-
stress scenario. To create a high-acuity situation, sev-
eral stressors were added to the scenario. Auditory
noise was introduced by setting the volume and
alarms on monitors at maximum and by having con-
stant 2-way radio communication noise. A socio-
evaluative stressor was introduced by an actor, play-
ing the role of patient’s partner, presenting as visibly
distressed and challenging the participants’ actions
and decisions. Patient presentation and treatment ex-
pectations for the scenario were developed by con-
sensus with 4 experts in the field of prehospital care.
Clinical performance was videotaped and scored on a
checklist of specific actions and a global rating of
performance. The paramedics also completed patient
care documentation after each scenario, and the no-
tations were scored for accuracy and completeness.
44
Twenty-two advanced-care paramedics, 17 men
and 5 women, from regional land and air ambulance
services in Canada took part in the study. Advanced-
care paramedics function within nationally defined
core competencies
45
and perform delegated medical
acts such as electrocardiogram acquisition and inter-
pretation, advanced life support procedures such as
tracheal intubation, and administration of emer-
gency medications that require dosage calculations.
Results
In this sample, 27.3 percent of the paramedics
scored in the no-to-low trauma symptom range, 9.1
percent scored in the moderate range, 13.6 percent
scored in the high range, and 50 percent scored in the
severe range. Posttraumatic stress did not correlate
significantly with either the anxiety or the cortisol
responses to the scenarios.
46
The paramedics reported greater anxiety and had
higher cortisol responses to the high-stress scenario
than the low-stress scenario. Correspondingly, scores
on the global rating of performance were signifi-
cantly lower in high-stress scenarios than in low-
stress ones (pⱕ.05); however, there was no differ-
ence on the checklist scores between the low- and
high-stress scenarios. Further, paramedics demon-
strated a higher number of commission errors (re-
porting information and procedures that were not
part of the scenarios) after high-stress scenarios.
There were no differences in omission errors (failing
to report information or actions that were part of the
exercise) between the two scenarios.
44
The paramedics’ posttraumatic symptom scores in
this study were not significantly associated with any
of the performance measures. It is possible that the
absence of association was related to sample size, as
correlations were high (rⱖ.30) but did not reach
statistical significance.
Study 4: PTSD, Acute Stress, and
Performance in Police Communicators
This study sought to gain better understanding of
the experiences of psychological distress and physio-
logical stress in a relatively unexamined group of
emergency responders, the police communicators.
PTSD, Acute Stress and Performance
188 The Journal of the American Academy of Psychiatry and the Law
Communicators responded to simulated 911 calls
from members of the public in a large computer
room designed to resemble an active dispatch center
with the sounds of other communicators in the back-
ground. An initial call was routine, followed by a call
that contained strong emotional content. The partic-
ipants were required to document the information
that was conveyed during the call. Immediately after
the scenario, the communicators were required to
complete a series of tests tapping into cognitive abil-
ity. In a Stroop-like task, participants had to read, as
fast as possible without making errors, the words in a
chart, regardless of the font type (e.g., LARGE large
SMALL should be reported as “large, large, small”).
In a more complex version of the chart task, partici-
pants were required to report the words as fast as
possible without making errors, but based on the
font rather than the word itself (e.g., LARGE large
SMALL should be reported as “large, small, large”).
The participants also completed a spelling test of
commonly used words in police communications,
and a test of the
␣
-codes alphabet (e.g., when hearing
the letter “a”, the correct response is “alpha”).
One hundred thirteen police communicators were
recruited from both rural and urban areas and were
employed by both provincial and municipal policing
services. Communicators ranged in age from 24 to
61 (mean, 40.9, SD 8.2) and had worked as commu-
nicators from 1 to 35 years (mean, 12.7, SD 8.4).
6
Results
Using the conservative diagnostic cutoff for PTSD
on the IES-R of 33 suggested by Creamer and col-
leagues,
47
31 percent of the sample had symptoms of
traumatic stress that met the criteria for PTSD, a rate
considerably above those reported in the literature
for both female and male police officers.
2,48
Performance on the complex chart task was signif-
icantly worse after the high-stress scenario and the
time to complete the task was significantly longer
than after the low-stress scenario. There were no dif-
ferences in the spelling, less complex chart naming or
the
␣
-code performance between the low-stress and
the high-stress scenarios. Because the high-stress sce-
nario followed the low-stress scenario, practice ef-
fects may have damped the effect size attributable to
stress.
Levels of PTSD symptoms were significantly asso-
ciated with greater errors in
␣
codes (r⫽0.205; pⱕ
.05) after the high-stress scenario but not after the
low-stress scenarios (unpublished data). They were
not associated with other measures of performance.
PTSD symptoms were associated with greater anxi-
ety levels after the scenario (r⫽.32, pⱕ.001), but
not with cortisol levels.
Discussion
Consistent with previous research, individuals in
this series of four studies involving emergency service
professionals reported high levels of exposure to po-
tentially traumatizing events, and correspondingly
high levels of posttraumatic stress symptoms, relative
to others in the general population. Percentages of
individuals reporting symptoms on the Impact of
Events Scale–Revised in the severe range, which is
consistent with a diagnosis of PTSD, were 19 percent
for police recruits,
40
19 percent for child protection
workers,
7
50 percent for paramedics,
46
and 31 per-
cent for police communicators.
6
When scores in the
high range are considered, the percentage of these
workers who were affected by traumatic stress symp-
toms was considerably higher. Clearly, this is a con-
cern for workers, the organizations in which they are
employed, and society as a whole.
Previous research has demonstrated associations
between PTSD and specific performance deficits in
individuals without comorbid mental health prob-
lems. For instance, PTSD has been associated with
deficits in verbal memory
17
and focused attention.
23
In the current series of studies, PTSD was not asso-
ciated with global performance indicators in police
recruits or paramedics. However, it was associated
with performance deficits on a verbal memory task in
police communicators after high-stress scenarios, but
not low-stress scenarios. Thus, PTSD may have a
greater influence on performance in high-stress situ-
ations than in low-stress ones.
Incidents for which emergency workers are called
to respond are characterized by heightened emotion,
violence, and injury. In short, they are highly stress-
ful. Three of the studies presented in this article (po-
lice recruits, child protection workers, and police
communicators) demonstrated that those individu-
als who reported higher levels of PTSD symptoms
also reported higher levels of subjective anxiety dur-
ing high-acuity simulations. This finding is perhaps
not surprising, given that the high-acuity simulations
were likely to be reminiscent of the events that led to
the development of PTSD in workers.
Regehr and LeBlanc
189Volume 45, Number 2, 2017
This association between trauma response and
acute stress is vital in the emergency services, consid-
ering growing evidence that performance is impaired
when individuals facing high demands exhibit ele-
vated stress responses.
29
With the exception of one
study (police recruits), we found that high-acuity
events and the stress responses that they engender are
associated with heightened assessment of risk in child
protection workers,
43
decreased performance on
complex cognitive tasks performed under time pres-
sures in paramedics and police communicators;
46
in-
creased commission errors and decreased global
functioning in paramedics;
44
and verbal memory im-
pairments in police communicators (unpublished
data). This is consistent with previous findings from
our own studies as well as those of other researchers
(summarized in Table 1). For instance, paramedics
exposed to high-stress events show impairments in
the ability to calculate drug dosages, to provide car-
diac resuscitation, and to recall pertinent details from
clinical scenarios.
49,50
Further, anxious individuals
demonstrate impairments in verbal reasoning, espe-
cially on high-demand tasks, when compared with
individuals with low levels of anxiety
27
and are more
likely to interpret situations as threatening.
24–26
As noted earlier, levels of PTSD symptoms were
not associated with global performance in police re-
cruits or paramedics. However, these measures as-
sessed specific competencies on highly learned tasks.
They perhaps do not reflect the influence of PTSD
on more complex clinical decision-making. An un-
expected finding related to PTSD and professional
judgment occurred in the child protection worker
study. In this study increased levels of PTSD symp-
toms were associated with a reduced tendency to
judge that a child was at risk of abuse. Previous re-
search has determined that emotional arousal nar-
rows and focuses attention, reducing the number of
cues to which the individual attends.
51
Individuals
with negative mood states are not only less likely to
consider a wide range of information, but they are
also more likely to take risks. We concluded that this
finding may suggest that workers with PTSD be-
come inured to tragedy and risk or that they filter out
information leading to a determination of risk.
42
This is clearly an area where more research is needed.
Limitations
As we have indicated, there have been some incon-
sistencies in the findings of our four studies. This
may reflect complex variations in the influence of
PTSD and acute stress response to performance
based on the nature of the tasks as in each of the
studies individuals were given different tasks to re-
flect the nature of their jobs. It also may be due to the
limitations of small sample sizes in these studies, par-
ticularly the paramedic study, which are due to the
challenges of recruiting participants to a demanding
and time consuming study. For instance, in the para-
medic study the association between PTSD symp-
toms and performance was high (rⱖ0.30), but did
not reach statistical significance. Further, this study
relied on self-report measures of PTSD symptoms
and did not include clinical diagnostic interviews,
which may limit the generalizability to clinical
assessments.
A clear limitation of these studies is that they rep-
resent attempts to simulate realistic workplace situa-
tions and evaluate performance in a standardized
manner. The methodology is based on a model that
is well known in medical education. For instance, the
use of standardized patients has been found to ensure
consistency in patient presentation, allowing for
comprehensive assessment of clinical competence.
52
Nevertheless, although the scenarios did effectively
elicit stress responses, it is clear that simulations can-
not replicate the multiple factors that influence stress
and decision-making in real life situations. Thus,
these findings add to empirical data in this area and
Table 1 Associations Among PTSD, Acute Stress, and Performance
Acute Stress Posttraumatic Stress
Police recruits Subjective distress not correlated with performance No correlation between PTSD and performance
Cortisol positively correlated with performance
Child protection workers Acute stress associated with higher likelihood of
finding that a child is at risk
PTSD associated with less likelihood of finding
that a child is at risk
Paramedics Global performance lower during high-stress event No correlation between PTSD and performance
More commission errors after high-stress event
Communicators More errors on complex tasks after high-stress event PTSD associated with decreased performance
in high-acuity scenarios
PTSD, Acute Stress and Performance
190 The Journal of the American Academy of Psychiatry and the Law
are a step beyond laboratory studies conducted on
general populations, but we cannot be certain that
the results accurately reflect performance in the
workplace.
Conclusion
Posttraumatic stress has been recognized, first in
the scholarly literature and more recently in legisla-
tion governing workers’ compensation, as being
likely consequences of exposure to traumatizing
events in emergency service work. Forensic psychia-
trists and other forensic mental health practitioners
are often called on to assess the extent of injury
caused by this traumatic exposure and the degree to
which the injury impairs an individual’s ability to
perform the duties required by their profession.
13,14
The results of this series of studies suggest, however,
that the relationship between PTSD and perfor-
mance is complex. That is, we did not find evidence
that PTSD has a direct impact on global perfor-
mance on tasks for which emergency responders are
highly trained. However, PTSD may affect assess-
ment of risk in situations that require professional
judgment. Further, the impact of PTSD on perfor-
mance and decision-making may be mediated by
acute stress responses. That is, individuals experienc-
ing posttraumatic stress symptoms report higher lev-
els of acute stress when faced with high-acuity situa-
tions. Acute stress in these studies is associated with
performance deficits on complex cognitive tasks, ver-
bal memory impairment, and heightened assessment
of risk. Given the nature of the work environment
encountered by emergency service occupations, psy-
chiatric assessments of disability associated with
PTSD must consider situationally provoked stress in
tandem with PTSD. This research not only has im-
plications for assessment, but also for prevention.
Preparation and support for workers in these envi-
ronments must go beyond the knowledge and
skills that they need in their work, to include train-
ing that assists them in managing acute stress re-
actions that may adversely affect their perfor-
mance and well-being.
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