Affiliations: Faculty of Pharmacy, Laval University, Québec, Que, Canada | URESP, Centre de recherche FRSQ du CHA universitaire
de Québec, Québec, Que, Canada | Department of Social and Preventive Medicine, Faculty
of Medicine, Laval University, Québec, Que, Canada | Department of Rehabilitation, Faculty of Medicine,
Laval University, Québec, Que, Canada | Interdisciplinary Research Group on Work Organization
and Health, Laval University, Québec, Que, Canada | Department of Industrial Relations, Faculty of Social
Sciences, Laval University, Québec, Que, Canada
Note: [] Address for correspondence: Dr. Clermont E. Dionne, URESP,
Centre hospitalier affilié universitaire de Québec, 1050, Chemin
Ste-Foy, Québec, G1S 4L8, Canada. Tel.: +1 418 682 7511, ext. 4675; Fax:
+1 418 682 7949; E-mail: [email protected]
Abstract: OBJECTIVE: This study investigated gender-specific interaction
between effort-reward imbalance and video display unit (VDU) postural risk
factors at work on the incidence of self-reported musculoskeletal symptoms in
the shoulder-neck, lower back and upper limbs regions. PARTICIPANTS: A cohort of 2,431 VDU users – consisting of
white-collar workers in three Canadian public service organizations – was
assessed on postural risk factors and effort-reward imbalance at work. METHODS: After a mean follow-up time of three years, the six-month
incidence proportion of musculoskeletal symptoms in each body region was
measured. Interaction was estimated with the attributable proportion of cases
due to interaction. RESULTS: For women, two significant attributable proportions due to
interaction between effort-reward imbalance and postural risk factors were
observed in the shoulder-neck (64%) and upper limbs (57%) regions, while an
interaction of 25%, although not significant, was observed in the lower back.
No interaction was observed for men. CONCLUSIONS: This interaction means that, among women, when
effort-reward imbalance and postural risk factors are simultaneously present,
the incidence of musculoskeletal symptoms is greater than the sum of effects of
the individual factors. Successful interventions on either one of these
exposures would thus have the supplemental benefit of preventing cases due to
interaction.
