relationship between organisational safety culture dimensions and crashes
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Relationship between organisational safety culturedimensions and crashesSakineh Varmazyara, Seyed Bagher Mortazavib, Shirazeh Arghamic & Ebrahim Hajizadehd
a Department of Occupational Health Engineering, Faculty of Medical Sciences, TarbiatModares University and Qazvin University of Medical Sciences, Tehran, Iranb Department of Occupational Health Engineering, Faculty of Medical Sciences, TarbiatModares University, Tehran, Iranc Department of Occupational Health Engineering, Zanjan University of Medical Sciences,Zanjan, Irand Department of Biostatistics, Faculty of Medical Sciences, Tarbiat Modares University,Tehran, IranPublished online: 10 Dec 2014.
To cite this article: Sakineh Varmazyar, Seyed Bagher Mortazavi, Shirazeh Arghami & Ebrahim Hajizadeh (2014): Relationshipbetween organisational safety culture dimensions and crashes, International Journal of Injury Control and Safety Promotion,DOI: 10.1080/17457300.2014.947296
To link to this article: http://dx.doi.org/10.1080/17457300.2014.947296
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Relationship between organisational safety culture dimensions and crashes
Sakineh Varmazyara, Seyed Bagher Mortazavib*, Shirazeh Arghamic and Ebrahim Hajizadehd
aDepartment of Occupational Health Engineering, Faculty of Medical Sciences, Tarbiat Modares University and Qazvin University ofMedical Sciences, Tehran, Iran; bDepartment of Occupational Health Engineering, Faculty of Medical Sciences, Tarbiat ModaresUniversity, Tehran, Iran; cDepartment of Occupational Health Engineering, Zanjan University of Medical Sciences, Zanjan, Iran;
dDepartment of Biostatistics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
(Received 1 March 2014; accepted 18 July 2014)
Knowing about organisational safety culture in public transportation system can provide an appropriate guide to establisheffective safety measures and interventions to improve safety at work. The aim of this study was investigation ofassociation between safety culture dimensions (leadership styles and company values, usage of crashes information andprevention programmes, management commitment and safety policy, participation and control) with involved self-reported crashes. The associations were considered through Spearman correlation, Pearson chi-square test and logisticregression. The results showed an association among self-reported crashes (occurrence or non-occurrence) and factorsincluding leadership styles and company values; management commitment and safety policy; and control. Moreover, itwas found a negative correlation and an odds ratio less than one between control and self-reported crashes.
Keywords: safety culture; public transportation; crash
1. Introduction
Safety culture is a subset of organisational culture (Cooper,
2000) which is the values shared among organisation mem-
bers about what the organisation has (i.e. policies and regu-
lation), what people do (i.e. safety-related behaviours) and
how people feel (Cooper, 2000; Wiegmann, von Thaden,
& Gibbons, 2007). Safety culture affects attitudes and
safety-related behaviour of the members of an organisation
(Cooper, 2000; Wu, Lin, & Shiau, 2010), employees’
health and safety (Fernandez-Muniz, Montes-Peon, &
Vazquez-Ordas, 2007) and safety consequences such as
injuries, fatalities and other incidents (Wu, Lin, & Shiau,
2009).
Commitments to safety in organisations by upper
management provide resources to develop and implement
safety measures. Therefore, beliefs, attitudes and practices
emphasise on minimum exposure of employees to
hazards. Moreover, the attitudes of company to safety and
precautions have negative effects on accident rates (Dorn,
2008).
1.1. Studies on the relationship between safe practices
and crash involvement
Pertaining to driving practices and accident, the findings
indicated that unsafe driving behaviours and higher crash
involvement rates were among work-related drivers in
comparison with drivers who use their own vehicles. The
higher rates of work-related crashes have been reported
due to fewer check practices being performed, such as
water in the radiator and pressure on the tyres. Also, some
evidences showed that the transportation fleet safety poli-
cies and practices and safety climate perceptions in place
within each organisation had a positive impact on the
drivers’ behaviour (Newnam, Watson, & Murray, 2002;
Wills, Watson, & Biggs, 2004). Some studies showed a
significant negative correlation between traffic safety,
work safety, violations and errors with the number of acci-
dents among professional drivers (Dorn, 2008; €Ozkan &
Lajunen, 2005). Other studies have shown that strong
safety culture resulted in higher safety climate perception
among the members, which can predict their perceived
safe behaviours (Mart�ınez-C�orcoles, Gracia, Tom�as, &
Peir�o, 2011). Finally, unrealistic time schedules of compa-
nies contributes to crash involvement, and in fact time
limitation increases crash risk (Dorn, 2012).
As the safety culture indicators are related to acci-
dent rates (Itoh, Andersen, & Seki, 2004), it is a piv-
otal factor to achieve organisational safety (Naevestad,
2010). On the other hand, little research has been con-
ducted about the relationship between safety culture in
public transportation and crashes, the main object of
this research was to investigate the relationship
between organisational safety culture dimensions and
self-reported crash involvement (the occurrence and
non-occurrence).
*Corresponding author. Email: [email protected]
� 2014 Taylor & Francis
International Journal of Injury Control and Safety Promotion, 2014
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Table 1. A summary of the exploratory factor analysis results.
Factors Items Factor loading Variance explained Eigenvalues >1
Leadership stylesand companyvalues (10 items)
(1) In this company, thereare safety instructions forworking with vehicles.
0.48
(2) My supervisor encouragesdrivers to offer their suggestionsto improve transport safety.
0.55
(3) My supervisor will provideexplanations about the safetransport objectives and programmes.
0.67
(4) My supervisor will identifymy work errors and teachme to correct them.
0.49
(5) The company gives importanceto the sincerity and participationof all drivers in collecting informationabout driving crashes.
0.69 34.6 14.5
(6) The company gives importanceto drivers’ initiative in findingnew solutions to safe transport.
0.48
(7) The company gives importanceto drivers’ collaboration andparticipation to promote safety.
0.41
(8) Drivers are informed aboutsafety rules and instructions.
0.66
(9) The objectives, benefits andproblems related to safe and unsafetransport are described to drivers.
0.48
(10) Meetings are held to informthe drivers about the potentialhazards of driving crashes and onhow to prevent them.
0.65
Usage of crashes informationand Prevention programmes(7 items)
(11) Training courses are held fordrivers about work-related health issues.
0.44
(12) In this company, specialisedtraining courses are held about theuse of tools and safety equipment.
0.70
(13) Crash prevention programmesare set in accordance with theanticipated hazards.
0.67
(14) Crash prevention programmesare shared with drivers.
0.65
(15) The results of driving crashinvestigations are used to solvetransport problems.
0.50 5.35 2.24
(16) The results of driving crashinvestigations are used to informthe drivers about the consequencesof breaking rules.
0.48
(17) The results of driving crashinvestigations are used to determinetraining demands and programmes.
0.44
Management commitmentand safety policy (6 items)
(18) The company managers providefinancial and human resourcerequirements for the implementationof safety principles.
0.66
(continued)
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2. Methods
2.1. Design of the questionnaire, participants
and procedure
The results of the previous studies can be used to develop a
new questionnaire (Guldenmund, 2007). Thus, safety cul-
ture questionnaire (SCQ) derived from the published papers
available in the literature (D�ıaz-Cabrera, Hern�andez-Fernaud, & Isla-D�ıaz, 2007; Fernandez-Muniz et al., 2007;
Wiegmann et al., 2007) thesis (Chenhall, 2010) and some
occupational health professors, PhD students and Health,
Safety and Environment (HSE) experts offered questions.
In this study, 628 bus drivers were randomly selected
by line supervisors of the bus company based on person-
nel code. An identification code was added to the
questionnaire (demographic and safety culture) for match-
ing the responses to assess repeatability. The researchers
explained the purpose of the study in a session with driv-
ers and ask them to complete the questionnaires. The
majority of drivers (n D 556, 88.5%) agreed to participate
the in study; the response rate was compatible.
Some studies (Hours et al., 2008; Taylor & Dorn,
2006; Varmazyar, Mortazavi, Arghami, & Hajizadeh,
2013) have shown that diseases and family problems can
result in crashes. 388 subjects (69.8%) were excluded
from the study due to fatigue, taking medication, some
disease and family problems. Thus, 168 (30.2%) question-
naires were examined to determine the role of safety cul-
ture in crashes.
Table 1. (Continued )
Factors Items Factor loading Variance explained Eigenvalues >1
(19) In this company, drivers’ safetyis important in the workplace.
0.68
(20) In this company, the managersbelieve it is their duty to payattention to the vehicle safety.
0.60 4.56 1.91
(21) In this company, managers discusssafety issues of the current programmeswith drivers in the meetings.
0.62
(22) The company has its own specialoperational policies and procedurein the context of health and safetytransport.
0.48
(23) The company tries to makethe drivers satisfied about the safetyof transport (vehicle and route).
0.41
Participation (3 items) (24) The drivers’ experiences who havebeen involved in crashes are usedto identify better solutions forsafe transport.
0.53
(25) Drivers’ opinions and suggestionsare used in creating instructionsfor safe transport.
0.57 3.93 1.65
(26) When the safety decision is madein company, meetings are heldbetween officials and drivers toincrease motivation in drivers.
0.54
Control (3 items) (27) In this company, drivingcrashes are reported, recorded,and analysed.
0.71
(28) The previous successfulprogrammes and solutions areexamined to solve transport problems.
0.41 3.22 1.35
(29) To ensure the effectiveperformance of the company,technical and safety inspectionsare regularly performed on all thevehicles and routes.
0.46
Note: Extraction method: principal axis factoring; rotation method: varimax with Kaiser normalisation � arotation converged in 18 iterations.
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2.2. Measures
2.2.1. Demographic and crash information
Drivers were asked to fill out a questionnaire which con-
tained items about age, education, marital status and the
number of all crashes at work over the last three years.
Drivers’ age ranged from 30 to 50 years with mean 39.3
§ 5.1 years. All participants were male and 99.4% were
married. 63.7% of drivers had high school or higher
degrees. The mean score and standard deviation of
involvement in crashes in the last three years were
2.9 § 3.1.
2.2.2. Validity, reliability and determination of safety
culture dimensions
Face validity (judgment about syntax, organisation and
appropriateness of 64 items of the primary questionnaire)
(DeVon et al., 2007), content validity ratio (CVR)
(surveying necessity of items) and content validity index
(CVI) (score for the entire instrument) (Lawshe, 1975)
have been investigated by 15 experts. CVR scores ranged
from 0 (not necessary) to 2 (necessary). The experts’
panel included occupational health professors and PhD
candidates, HSE (health, safety and environment) and
psychologists. CVR is calculated according to the follow-
ing formula:
CVR ¼ ne ¡ N2
N2
where ne is the number of experts who rated an item as
‘essential’ and N is the total number of experts.
According to the criterion values provided by Lawshe
(1975), acceptable range CVR is equal to or larger than
0.49 for the 15 panelists. In other words, CVR obtained
from the above formula should be equal or larger than the
CVR value of 0.49 for each item (Lawshe, 1975). Based
on the CVR value, 22 items with CVR <0.49 were
dropped.
CVI is simply the mean score of those retained items
with CVR �0.49 according to the following formula
(DeVon et al., 2007; Lawshe, 1975). CVI was obtained as
0.762 that showed an acceptable level.
CVI ¼P
CVR for all retained items
retained items numbers
For test�retest reliability, 35 subjects were asked to fill
out the questionnaire for the second time after almost two
months. Pearson correlation (0.81) was calculated for
judging the correlation between the retest and the initial
study, which is acceptable (the value �0.70 was consid-
ered satisfactory).
The SCQ 42 items were filled out by drivers on a five-
point Likert scale (0 D completely disagree to 4 D
completely agree). Exploratory factor analysis (EFA) by
principal axis factoring (PAF) with varimax rotation
(Dorn, 2008) was used to identify the number and nature
of the factors of SCQ. In factor selection, the eigenvalue
rule �1 (Diaz-Cabreraet al., 2007) and the scree plot test
(Chenhall, 2010; Vandenberg, 2009) were used. The num-
ber of items representing each factor was required to reach
the minimum value of three variables in that factor and a
minimum factor loading of 0.40 per item (Chenhall,
2010). Accordingly, among the ten factors exited from
EFA, five factors (including eight items) that are com-
posed of only one or two items are not interpreted (Diaz-
Cabrera et al., 2007) so, those were excluded from the list
of factors. Consequently, five key dimensions (including
29 items) related to safety culture were obtained: (1) lead-
ership styles and company values; (2) usage of crash
information and preventive programmes; (3) management
commitment and safety policy; (4) participation and (5)
control (see Table 1). The internal consistency of the
questionnaire (items and factors) were calculated using
Cronbach’s alpha coefficients (Cox & Cheyne, 2000),
(see Table 2).
2.2.3. Surveying the relationship between safety culture
dimensions and crashes involvement
The Pearson chi-square, Spearman correlation tests and
logistic regression were used to examine the relationship
between the mean of the items constitutive each of safety
culture dimensions in Likert scale (that are ordinal varia-
bles) and self-reported crashes involvement (134 drivers
experiencing crash versus 34 drivers not being involved in
any crashes/accidents) as nominal variable.
Table 2. Mean scores of items for the SCQ factors and reliabilitystatistics by factor.
Factors Mean SDCronbach’s aeach factor
Cronbach’s atotal items
Leadership stylesand companyvalues (10 items)
11.7 9.4 0.90
Usage of crashesinformation andPreventionprogrammes(7 items)
7.4 6.3 0.86 0.95
Managementcommitmentand safety policy(6 items)
5.9 5.3 0.81
Participation(3 items)
2.5 2.9 0.77
Control (3 items) 11.7 3.0 0.71
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3. Results
3.1. Self-reported crashes involvement
Frequency and percentage of drivers involved in all self-
reported accidents of last three years in study sample (n D168) are shown in Table 3. Exactly, 29.8% drivers were
involved in four crashes or more in the last three years.
3.2. Association between safety culture dimensions
and crashes involvement
Based on the Pearson chi-square test, some of the safety
policies and practices in organisation such as leadership
styles and company values, management commitment
and safety policy and control have a significant associa-
tion with crashes involvement. There is also a signifi-
cant negative correlation between control, as one of the
safety culture dimensions, and crashes involvement
based on Spearman test. The Wald test showed that the
logistic coefficient (B) of control is not equal to zero.
The Exp(B) is the odds ratio associated with each pre-
dictor that Exp(B) values less than one of control shown
reduction of crashes by this variable (see Table 4).
4. Discussion
The main objective of this study was to investigate the
relationships between organisational safety culture dimen-
sions with self-reported crashes involvement.
Three dimensions of safety culture including leadership
style, company values; management commitment, safety
policy; and control are related to crash involvement. So,
safety policies and practices of the aforementioned dimen-
sions (leadership styles, company value; management com-
mitment, safety policy; control) may have an effect on
driving behaviour and consequently reduce crashes. It is
recommended to encourage drivers to improve safety levels
and their collaboration and participation in recognizing
hazards and crash prevention. Organizations should provide
financial and human resources of safety, consider vehicles
safety, record and analysis crashes and inspect safety of
vehicles and routes. In a similar research conducted by
Newnam et al. (2002), they found that organization safety
policies and practices influence driving behaviours in work
were related vehicles more than personal vehicle. Indeed,
lack of work-related vehicle checking practices lead to
increase in crashes (Newnam et al., 2002). Similarly,
inverse relation was reported between traffic safety and
work safety with violations and errors (Dorn, 2008). Also,
there was a significant positive correlation (r D 0.42)
between fleet safety climate perceptions and the safety of
work-related driver behaviour (Wills et al., 2004) and also
between safety culture (r D 0.13) and safety climate (r D0.37) with safety behaviours in nuclear power plant
(Mart�ınez-C�orcoles et al., 2011). One of the studies con-
ducted by Darby, Murray, and Raeside (2009) revealed
that attitude and behaviour scores had a statistically nega-
tive significant association with collision involvement
(Darby et al., 2009). Moreover, the studies of Dorn (2012)
and Oz et al. (2013) revealed that time limitation (poor
organisational safety culture or climate) contributes to fre-
quencies of violations, errors and crash involvement (Dorn,
2012; €Oz, €Ozkan, & Lajunen, 2013).
Management commitment to safety and organisational
safety culture can indirectly reduce unsafe behaviour by
developing a safety management system. On the other
hand, drivers’ involvement and participation influence on
Table 3. Number of drivers involved in crashes in past threeyears.
Percentage Number of drivers Number of crash involvement
20.2 34 0
17.3 29 1
17.9 30 2
14.8 25 3
29.8 50 �4
Table 4. Relationship between safety culture dimensions and self-reported crashes involvement.
Pearson chi-square Logistic regression
FactorsSpearmancorrelations Value df
Sig(p-value) B Wald Sig Exp(B)
95% CI forExp(B) lower�upper
(1) Leadership styles and company values ¡.056 48.8�� 33 0.037 .031 .009 .92 1.03 0.54¡1.94
(2) Usage of crash information andPrevention programmes
¡.107 20.4 23 0.616 ¡.048 .020 .88 .95 0.49¡1.85
(3) Management commitment andsafety policy
¡.059 36.9�� 21 0.017 .035 .015 .90 1.04 0.59¡1.81
(4) Participation ¡.015 12.4 11 0.327 .227 .676 .41 1.25 0.73¡2.16
(5) Control ¡.182� 23.1�� 12 0.027 ¡.645 6.51 .01� .52 0.32¡0.86
�Correlation is significant at the 0.05 level.��Chi-square is significant at the 0.05 level with respect to p-value.
International Journal of Injury Control and Safety Promotion 5
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employees safe practices directly. Consequently, crash
rate will be decreased (Fernandez-Muniz et al., 2007).
Concerning the organisational aspects such as safety
culture leading to the reduction of violations (Cacciabue,
2007), the results of this study indicated that there is a
significant inverse correlation and odds ratio less than
one between control dimensions of safety culture and
self-reported crashes involvement. It can be concluded
that the information obtained from the analysis of crashes
is effective in the prevention of further crashes. In addi-
tion, measures such as investigation of previously held
programmes about safety and the technical and safety
inspections of the vehicles and routes may reduce driving
crashes.
5. Limitation
In relation to the study sample, there was no representa-
tion of female drivers. Because of social culture and job
difficulty, females do not work on buses in Iran. This
study was only implemented for day shift drivers and only
in the governmental transportation system.
6. Conclusion
A variety of aspects of organizational safety culture
including managers’ behavioural patterns, managers’ atti-
tudes and activities, drivers’ suggestions and solutions
about this issue could decrease the number of crashes.
Also, the identification of hazards and the implementation
of safe measures, recording and the analysis of crashes,
the involvement of the drivers to solve the problems, and
revision of previous programmes play important roles in
reducing the number of crashes. Consequently, attention
to each of the above-mentioned aspects may contribute to
the decline of accidents. So, as a suggestion, future
research can investigate the influence of each of the safety
culture dimensions to reduce the accidents.
Acknowledgements
The authors express their gratitude to the senior managers of BusCompany and the middle managers and HSE experts in TehranTransportation Bus Company. We thank Mr. Maryam KeramatKar, PhD student at the University of Otago, for proof reading ofthe manuscript.
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