Attributions, Stress,
and
Work-Related Low Back Pain
George Byrns, MPH, Ph.D., CIH
Illinois State University
Background & Significance

LBP WC claims in the US (1992)
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–

Risk factors
–

16% of claims
33% of costs (>$49 billion)
individual, job-related, physical, & psychosocial
In spite of mechanization, LBP is still a major
source of disability
Physical Stain Model
Exposure
Capacity
Dose
Response
Conceptual Model for Attributions as a Risk Factor for LBP
Physical demand
W
o
r
k
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v
I
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m
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Low Back Pain
Function
Injury
Attributions
Resources
Knowledge of
Back Safety
Psychological demand
Psychological Stress
The Dimensions of Resources
Individual characteristics
R
e
s
o
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r
c
e
s
Age
Gender
Fitness
Body mass index
Education Coping skills
Smoking Prior LBP
Social environment
Job social support
Home social support
Safety climate
Management support
Implementation
What is an attribution?
Attribution: a natural human tendency to
see patterns or explain unfortunate events
 Attributions have 3 major dimensions:

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–
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locus of causation
stability/permanence
controllability
How are attributions & stress related?
External, permanent, uncontrollable factors
are expected to cause stress
 Attributions of LBP cause may affect:

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–
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the worker’s knowledge of back safety
perceived job control
likelihood of reporting LBP
How is stress related to LBP?

Prolonged muscle tension may
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–

Overload documented in neck & shoulders
–

overload muscle fibers
result in loss of blood flow to muscles
Also likely in low back
There may be other mechanisms as well
Hypotheses
H1: Persons knowledgeable in back safety
will attribute internal causes of LBP
(behavior)
H2: Less LBP in those high in back safety
knowledge.
H3: Perceived job control will be higher in
those who attribute internal causes of LBP
Hypotheses
H4: Workers with LBP will also report high
demands, low control & low social support.
H5:Workers with LBP are more likely to
attribute the cause to an external source.
Specific Aims
1. Measure the prevalence of LBP in garment
workers.
2. To observe & record postures & movements
of workers performing primary job tasks.
3. Measure worker stress using the Karasek
Demand-Control-Support model.
Specific Aims (cont)
4. Measure workers’ attributions of LBP
causation.
5. Use attribution theory in a new model to
explore the associations between worker
stress & LBP.
Research Design & Methods
Study design: cross-sectional
 Study population: a garment factory with
approximately 400, mostly white,
unionized, middle-aged women, & paid by
piece work
 Data collection: self-administered
questionnaire & direct observation

Research Design & Methods (cont)
Developed questionnaire & observation
checklist
 Developed new scales to measure
attributions & knowledge of back safety

Data analysis
Analysis of newly developed scales
 Univariate analyses
 Bivariate analyses
 Multivariate analyses

Results: Reliability & Validity
Karasek’s Demand-Control-Support Model
 Newly developed scales
 Observation results
 Comparison of attributions of
managers/supervisors & workers

Comparison of Workers &
Managers

Workers (79%) & managers (100%) attribute
LBP to worker actions
–

86% of workers & 31% of managers also blamed
work conditions
When asked which was most important
–
56% of workers said work conditions compared
to only 6% of managers
Results: LBP Prevalence
Any report of LBP last year: 63.7%
 LBP not due to sports or non-occ. causes
that limited movement or interfered with
work at home or on the job: 36.2%

Knowledge of Back Safety
Knowledgeable workers had high internal
attribution (OR = 4.6) p < 0.001
 Knowledgeable workers do not report less
LBP

Perceived Job Control
Higher control in workers with internal
attribution & job social support from the
supervisor
 Also age & income effects

Demand-Control-Support Model
LBP was only associated with high job
demand (OR = 2.5, p < 0.01)
 LBP was also associated with higher
income (OR = 2.4, p < 0.01)

Attributions & LBP
More LBP in workers attributing LBP to job
tasks (OR = 4.4, p < 0.001)
 Less LBP in workers with high supervisor
social support (OR = 0.25, p < 0.01)
 Also age & income effects

Limitations

Cross-sectional design
–
temporality, survivor bias
Recall bias
 Inter-rater agreement
 Unique study population
 Unmeasured variables

Discussion - Implications 1
Measure attributions before teaching back
safety
 Improve worker control

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attributional retraining
increasing social support
Discussion - Implications 2
Demand-Control-Support model may need
modification for use with LBP
 Attribution model works well for study of
LBP

Discussion - Future Research
Examine manager/supervisors & worker
attributions for presence of mismatch
 Use model in other occ. groups & other
outcomes
 Measure attributions at baseline & do a
longitudinal study

Implications of attribution on stress,
biomechanics, & LBP
If root cause of LBP is worker actions, need
improvements in risk communication
 If LBP is caused or contributed by work
conditions, need env. modification

Epilogue:
Expectancies: Cause & Responsibility
 Worker
is careless-> make worker careful
 Job is dangerous -> make worker careful
 Job is dangerous -> make the job safer
 Worker is careless -> make the job safer