Abstract
BACKGROUND:
Firefighters partake in and are exposed to a range of potentially traumatic events throughout their careers and the impact of such critical events could last a life time. Therefore, capturing such lifetime exposures is necessary for supporting firefighter health.
OBJECTIVE:
To estimate the prevalence of critical incidents in firefighters across Canada and determine whether the number of critical events varied based on age, gender, years of service; and to integrate our prevalence estimates using meta-analysis with previous studies to provide a pooled estimate.
METHODS:
We recruited 464 firefighters. Firefighters were asked to complete a self-report Critical Incident Inventory (CII) survey that included questions on exposure to critical events throughout their firefighting careers. Individual CII items were summarized as percentages, number of exposures, the total number and percentages of exposures to each of the six CII sub-scales. We also performed a multivariate enter regression analysis with the CII total score as dependant variable, and age, gender, years of service as independent variables, to estimate if the number of critical incidents among firefighters varied based on age, gender and years of service.
RESULTS:
Among the 390 full-time firefighters, 376 (96.4%) indicated exposure to some type of critical incident. More specifically, 351 (90%) reported a “respond to incident involving one or two deaths”, and 314 (81%) reported a “respond to incident involving multiple serious injuries”. Age, gender and years of service accounted for only 37.4% of the variance in the number of critical incidents among firefighters. In addition, our pooled estimate results of previous similar studies indicated an overall prevalence estimate of critical incident exposures was 93.40% (4 studies, 1725 of 1877 firefighters, 95% CI: 82.26 –99.30).
CONCLUSIONS:
Nearly all (96.4%) firefighters were exposed to some form of critical event over the span of their entire firefighting careers. Age, gender and years of service accounted for one-third of the variance in the number of critical incident exposures among firefighters.
Introduction
Critical incidents are used in reference to traumatic event exposures that are sudden, overwhelming and exceed beyond an individual’s normal coping skills and may ultimately lead to adverse mental health consequences [1–3]. These types of critical incidents and psychological stresses for public safety personnel such as firefighters, pertain to injury or personal loss, exposure to burned bodies, life-threatening situations, failed rescue efforts or death of co-workers [4–9].
Critical incident and duty-related trauma exposures among firefighters have been reported across various contexts [3, 11]. MacDermid et al. (2018) studied 293 Canadian firefighters (285 males and 8 females) and found that 85% of firefighters had been exposed to some type of critical incident in the previous 2-months. In addition, “response to incident involving one or two deaths” (64%), and “direct exposure to blood and body fluids” (53%), were identified as the top two duty related incidents firefighters were exposed to throughout a 2-month period [3]. Similarly, in Brazil’s study (2017) of 102 part-time Canadian volunteer firefighters (95 men, 7 women) on Prince Edward Island, 85% reported being exposed to at least one critical incident in the past 2 years [11]. Beaton et al. (1999) study of 625 Canadian firefighters (all males) reported that, exposure to suicides (39%) and dead on arrival (25%) were the top two duty related incidents that firefighters were exposed to throughout a 12-month period [5].
Firefighters partake and are exposed to a range of potentially traumatic events throughout their careers (12–15). Results from the available literature indicate that subjective experience of intense fear, helplessness, or horror in response to critical incidents have been shown as contributing factors to posttraumatic stress disorder [15]. Moreover, there is substantial evidence that individual perceptions, rather than objective descriptions, are what determine whether or not a potentially traumatic event will be critical [12]. In any case, the impact of critical events could last a life time, which is why assessing lifetime exposure is so important for supporting firefighter health. There is also a paucity of reports in the literature concerning the prevalence of critical incidents among female firefighters. Furthermore, critical incident exposures have been associated with general psychopathology and symptoms of post-traumatic stress disorder when controlling for age, gender and years of service [17]. Therefore, the current study was designed to: 1) estimate the prevalence of critical incidents in firefighters from across Canada; 2) determine whether the number of critical events varied based on age, gender, years of service; and 3) to integrate our prevalence estimates using meta-analysis with previous studies addressing the prevalence of critical incidents in firefighters.
Methods
Participants and data collection
The current study included results from a cross-sectional survey of firefighters from 160 different locations across Canada, including Prince Edward Island. The inclusion criteria for this study were that participants had to be Canadian firefighters (i.e., recruit, volunteer, career, captain and 1st rank; from across Canada) and those who provided a written consent. Other public safety personnel were not included in this survey. The recruitment strategies for this study involved online and in-person administration of the surveys. Firefighters completed the questionnaires in two formats: paper-based (distributed at conference Calgary, state of Alberta) and web-based (via an open-source survey tool, LimeSurvey –Hamburg, Germany) as emails were sent out to firefighter stations. All the firefighters were asked to complete a 24-item self-report Critical Incident Inventory (CII) survey, that included various questions on a series of exposures to critical events while performing firefighting duties throughout the entire careers. Ethical approval was secured for this study through our institution.
Critical Incident Inventory (CII)
The CII (firefighter specific) consists of six subscales: trauma to self, victims known to fire-emergency worker, multiple casualties, incidents involving children, unusual or problematic tactical operations, and exposure to severe medical trauma [2]. Each of the sub-scales are further divided into 2–6 items of potential critical incident exposures with a sum of 24 items [2]. The origins of the CII are part of a subset list relative to the broader list of potentially traumatic events (PTE). Firefighter demographics (age, height, weight, years of service) were also collected in the survey.
Firefighters were asked to report whether an event had occurred throughout their careers by indicating “No” or “Yes”, and whether it had occurred “one time,” “two times,” or “three or more times.” This enabled us to record the existence of an exposure (a dichotomous response as no/yes) and frequency of exposures (None, One time, Two times, Three or more times). A value of 0, 1, 2, or 3 was assigned to each response, respectively. The CII scale score ranges from (0 to 72) and is generated based on the summed scores.
Statistical analysis
Firefighter demographic characteristics (age, height, weight, years of service) were reported using means and standard deviations. Firefighters’ reports of critical incidents on individual CII items were summarized as percentages and number of exposures. In addition, the total number and percentages of exposures to each of the six CII sub-scales were also reported. We carried out a multivariate enter regression analysis with the CII total score (dependant variable) and age, gender, years of service (independent variables), to estimate if the number of critical incidents among firefighters varied based on age, gender and years of service. All the assumptions of multiple regression (tests of normality, heteroscedasticity, multicollinearity and linearity) were met prior to our regression analysis. Analyses were carried out using IBM SPSS Statistics software version 22.0 and a significance level of p≤0.05 was considered statistically significant. We also performed 2 meta-analyses including the findings of our study and other studies found in the literature that reported the prevalence of critical incidents in full-time firefighters (one was the overall prevalence and one was stratified by duration –up to one year). Relevant studies concerning the prevalence of critical incidents among firefighters were identified using the Embase, Medline and PubMed databases. Prevalence estimates were calculated, and study specific estimates were pooled using a random-effects model. The proportion (random-effects), their weighted proportions and 95% confidence intervals were summarized in forest plots. A software program (MedCalc software bvba, version 16.2.1) was used for statistical analyses.
Results
Sample
A total of 390 full-time firefighters (272 males and 118 females) from 160 locations across Canada and 74 volunteer firefighters from Prince Edward Island (68 males and 6 females) completed the survey (response rate 100%). The characteristics of the firefighters according to gender are displayed in Table 1.
Demographic characteristics
Demographic characteristics
Among the 390 firefighters, 376 (96.4%) indicated exposure to some type of critical incident as described by the CII. The mean and range of the CII experienced by the firefighters over the span of their entire firefighting careers were 30 and 0–72, respectively. The total number of firefighters exposed and times of exposure to each CII item, has been displayed in Table 2. Among the 390 firefighter respondents, 351 (90%) reported a “respond to incident involving one or two deaths”, 314 (81%) reported a “respond to incident involving multiple serious injuries”, 312 (80%) indicated a “direct exposure to blood and body fluids”, and 300 (77%) reported a respond to incidents involving removal of dead bodies. The most infrequent events reported were “use of deadly force by police at an incident” (7%) and “serious line of duty injury to self” (16%). Nearly one out of four firefighters (26%) reported “suicide or attempted suicide by fellow emergency worker”. Approximately one out of three firefighters (34%) and (39%) stated exposure to “line of duty death of a fellow emergency worker” and response to “incidents involving three or more deaths” respectively. Furthermore, nearly two out of three firefighters indicated exposure to “incidents involving severe threat to children” (63%), “incidents requiring police protection while on duty” (67%), “Prolonged extrication of trapped victim with life-threatening injuries” (64%) and exposure to “close contact with burned or mutilated victim” (68%). When stratified by sub-scales, “multiple casualties” and “trauma to self” were the two highest reported exposures 93% and 89% respectively (Table 4). Among the 74 volunteer firefighters from Prince Edward Island, 71 (96%) indicated exposure to some type of critical incident. The mean and range of the CII experienced by the firefighters over the span of their entire firefighting careers were 23.0 and 0–72, respectively. The total number of firefighters exposed and times of exposure to each CII item, has been displayed in Table 3. Among the 74 firefighter respondents, 66 (89%) reported a “respond to incident involving one or two deaths”, 57 (77%) reported a “respond to incident involving multiple serious injuries” and 53 (72%) reported a respond to incidents involving removal of dead bodies. The most infrequent events reported were “use of deadly force by police at an incident” (2.7%) and “line of duty death of a fellow emergency worker” (9.5%). When stratified by sub-scales, “multiple casualties” (91%), “trauma to self”, “Victims Known to Fire-Emergency Worker”, and Exposure to Severe Medical Trauma (all 81%), were top four reported exposures (Table 5).
Number of firefighters’ exposed and times of exposure to critical incidents based on each item (Canada)
Number of firefighters’ exposed and times of exposure to critical incidents based on each item (Canada)
Number of firefighters’ exposed and times of exposure to critical incidents based on each item (Prince Edward Island)
Number and percentages of firefighters’ exposure to each CII sub-scale (Canada)
Number and percentages of firefighters’ exposure to each CII sub-scale (Prince Edward Island)
Gender (males and females) and years of service were statistically significantly related (p < 0.05) to the number of critical incidents among firefighters (Table 6). Furthermore, age, gender and years of service accounted for only 37.4% of the variance in the number of critical incidents among firefighters.
Regression model for factors predicting critical incidents in firefighters in Canada (n = 386)
Regression model for factors predicting critical incidents in firefighters in Canada (n = 386)
Three previous studies including MacDermid 2018 (293 firefighters), Carleton 2018 (569 firefighters) and Beaton 1999 (625 firefighters), and the data from our current study (390 firefighters), were pooled. The overall prevalence estimate of critical incidents was 93.40% (i.e., four studies, 1725 of 1877 firefighters, 95% CI: 82.26–99.30; I 2 = 98.30%; Table 7). When stratified by duration (up to1-year), the pooled results demonstrated an estimate of 85.0% (2 studies, 781 of 918 firefighters, 95% CI: 82.62–87.3; I2 = 0.00%; Table 7).
Meta-analysis of the number of critical incidents among firefighters in Northern America
Meta-analysis of the number of critical incidents among firefighters in Northern America
CI; confidence intervals.
The current study used cross-sectional survey results from 160 different cities were identified 96.4% (376/ 390) of firefighters as having been exposed to some type of critical incident over the span of their entire firefighting careers. More specifically nine in ten firefighters reported a “respond to incident involving one or two deaths”. Furthermore, eight in ten reported a “respond to incident involving multiple serious injuries”, or a “direct exposure to blood and body fluids”. When stratified by sub-scales, exposures to “multiple casualties” and “trauma to self” were the two highest reported events experienced by firefighters. In addition, age, gender and years of service accounted for and explained one-third of the variance in the number of critical incident exposures among firefighters.
Our results are consistent with other studies that have indicated high critical incident exposures among firefighters. In Beaton et al.’s (1999) study of 625 Canadian firefighters, 85% (n = 531) indicated an exposure to at least one incident, with a mean number of 3.0±2.9 exposures [5]. Variations in the mean number of incident exposures in the Beaton et al. (1999) study (i.e., 3.0), compared to ours (i.e., 30.0), may be due to the differences in instruments used to capture critical incidents (Emergency Medical and Fire Incident reports vs. Critical Incident Inventory) or the time-frame (past 1 year vs. entire firefighting careers) in which firefighters were required to recall an exposure to a critical incident [5]. The use of Emergency Medical and Fire Incident reports in Beaton et al. (1999) study, did not allow for direct comparison of incident exposures with that of our current study. In the Carleton et al. (2018) study of 569 firefighters, 568 firefighters (99.82%) reported at least one traumatic exposure during their life time. The Life Events Checklist for the DSM-5 was used, which did not permit direct comparison with the current study, but did permit comparisons with exposures rates in the general population [12].
In Brazil’s study (2017) of 102 part-time volunteer firefighters on Prince Edward Island, Canada, 85% reported being exposed to at least one critical incident in the past 2 years [11]. Similar critical incident exposure rates were noted in our cohort of volunteer firefighters from Prince Edward Island (i.e., high –96%). The Brazil (2017) report of critical incidents was based on volunteer firefighters’ subjective interpretation of an exposure that constituted a critical incident, rather than the report of the 24 items (scenarios) on the established CII instrument [11]. This methodological variation complicates identifying the most/least frequently reported critical incidents among firefighters. In Monnier et al.’s (2002) study of 150 full-time professional US fire-emergency workers, approximately 62% (current study 90%) reported a respond to incident involving one or two deaths, 53% (current study 80%) indicated a direct exposure to blood and body fluids, and 49% (current study 81%) reported a response to an incident involving multiple serious injuries in the past 2 months [2]. Similarly, in MacDermid et al.’s (2018) study of 293 Canadian full-time firefighters, 64% (current study 90%) reported an incident involving one or two deaths, 53% (current study 80%) reported a direct exposure to blood and body fluids, and 33% (current study 81%) a response to an incident involving multiple serious injuries in the past 2 months [3]. The percentage of event exposures in the current results were higher than those of Monnier et al.’s (2002) and MacDermid et al.’s (2018), possibly due to using a larger sample size and the recall of an exposure to a critical incident over the span of firefighters’ entire firefighting careers. The higher rates were similarly reflected in our sub-group analysis (i.e. stratified by duration –up to1-year), in which the percentage of event exposures was 85.0% (2 studies, 781 of 918 firefighters, 95% CI: 82.62–87.3).
In Canada, women make up nearly 2.4% of all personnel in fire services [18]. Furthermore, exposure to critical incidents have been associated with various mental health problems after controlling for gender, age, and years of service [17]. Therefore, we assessed whether gender, age and years of service could be used to account for variance in the number of critical incident exposures in firefighters. Our multiple regression analyses (n = 386; 118 females) demonstrated that gender and years of service were significant, and with addition of age, our model displayed a 37.4% predictive value for the number of critical incident exposures in firefighters. With 1-year increase in years of services, the number of critical incident exposures increases by 1.2. Furthermore, we established that females, had decreased exposures of critical incidents by 3.56. We were unable to compare our results because we did not find studies that had assessed associations with age, gender, or years of service and the number of critical incidents among firefighters.
The current study strengths include using a large sample of firefighters from 160 different locations across Canada. Furthermore, the critical events inventory was administered and captured lifetime exposures. We had a high response rate; however, firefighters with critical incidents may have been off duty and therefore not sampled, leading to an under-represented the exposures. The current study was designed to describe exposures and did not quantify the impact of such exposures. Future studies should quantify the impact of the events simultaneous to exposure assessments and assess the impacts of health and work outcome in prospective longitudinal studies.
Conclusion
Nearly all (96.4%) firefighters in this sample were exposed to some form of critical event over the span of their entire firefighting careers. Most (nine out of ten) firefighters reported a responding to an incident involving one or two deaths. Furthermore, most (eight out of ten) also reported a responding to an incident involving multiple serious injuries, or a direct exposure to blood and body fluids. Age, gender, and years of service accounted for one-third of the variance in the number of critical incident exposures among firefighters. The results indicate that substantial portions of Canadian firefighters experienced critical events, therein, necessitating further emphasis on additional research.
Conflict of interest
None to report.
Funding
This work was funded by the Ontario Ministry of Labour (FRN #13-R-027).