Evaluating the impact of organizational interventions implemented as part of the Québec Healthy Enterprise Standard on physical and psychosocial work factors and work-related musculoskeletal problems

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Evaluating the impact of organizational interventions implemented as part

of the Québec Healthy Enterprise Standard on physical and psychosocial

work factors and work-related musculoskeletal problems

Mémoire

Karine Aubé

Maîtrise en santé publique

Maître ès sciences (M. Sc.)

Québec, Canada

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Evaluating the impact of organizational interventions

implemented as part of the Québec Healthy Enterprise

Standard on physical and psychosocial work factors

and work-related musculoskeletal problems

Mémoire

Karine Aubé

Sous la direction de :

Chantal Brisson, directrice de recherche

Clermont Dionne, codirecteur de recherche

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Résumé

Contexte : Les troubles musculosquelettiques liés au travail (TMST) comptent parmi les problèmes de santé les plus fréquents et coûteux chez les travailleurs. Les contraintes physiques et psychosociales au travail contribuent au développement des TMST. L’implantation d’interventions organisationnelles ciblant ces contraintes pourrait réduire ces expositions professionnelles délétères et ainsi diminuer les TMST. Deux des quatre sphères d’intervention de la norme québécoise Entreprises en Santé (NEES) visent à réduire les contraintes physiques et psychosociales au travail. Peu d'interventions ciblant ces deux contraintes ont encore été évaluées et aucune ne l’a été dans le contexte d'une norme. Objectifs : Dans 10 entreprises québécoises ayant implanté la NEES: 1) Mesurer les changements avant-après de la prévalence des contraintes physiques et psychosociales au travail et des TMST; 2) Examiner si les prévalences de ces trois indicateurs sont plus faibles parmi les participants exposés aux sphères d’intérêt; 3) Mesurer les associations transversales postulées par le cadre théorique guidant ce projet. Méthode : Il s’agit d’une étude utilisant des données mixtes avec un devis avant-après et un devis transversal. Les employés de 10 organismes ont complété un questionnaire avant (T1;n=2849) et 24-38 mois après (T2;n=2560) l’implantation de la NEES. Les contraintes physiques au travail ont été évaluées à l’aide de cinq items. Les contraintes psychosociales au travail ont été évaluées selon des modèles validés. Les TMST ont été mesurés à l’aide de quatre items adaptés du Questionnaire Nordique. Résultats : La prévalence d’une contrainte physique et de trois contraintes psychosociales était plus faible parmi les participants rapportant avoir été exposés aux interventions dans chacune des deux sphères d’intérêt. Aucune différence dans la prévalence des TMST n’a été observée parmi les participants exposés aux deux sphères simultanément. L'intensité des interventions pourrait expliquer ces résultats. De fortes associations transversales ont appuyé le cadre théorique utilisé dans ce projet.

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Summary

Background: Work-related musculoskeletal problems (WMSP) are amongst the most frequent and costly health problems experienced by the working population. Adverse physical and psychosocial work factors contribute to the development of WMSP. Workplace interventions targeting these factors may help reduce their prevalence and thus reduce WMSP. The Québec Healthy Enterprise Standard (QHES) targets four intervention areas, two of which aim to reduce adverse physical and psychosocial work factors. Few interventions targeting both these factors on WMSP outcomes have yet been evaluated and none in the context of a standard. Objectives: 1) Measure pre-post changes in the prevalence of adverse physical and psychosocial work factors and WMSP; 2) Examine if the prevalence of these adverse work factors and that of WMSP is lower amongst participants exposed to the QHES areas of interest; 3) Measure cross-sectional associations postulated by the theoretical framework guiding this project. Methods: This was a mixed-methods study with before-after and cross-sectional designs. Employees of 10 Québec organizations completed a questionnaire before (T1;n=2849) and 24-38 months following (T2;n=2560) QHES implementation. Participating organizations voluntarily adopted the standard and were responsible for implementing interventions. Physical work factors were measured with five items. Psychosocial work factors were assessed using items from validated models. WMSP were measured with four items adapted from the Nordic Questionnaire. Results: The prevalence of one adverse physical and three adverse psychosocial work factors was lower amongst participants who reported being exposed to interventions in each QHES area of interest. No difference in the prevalence of WMSP was observed amongst participants who reported being exposed to these two areas simultaneously. The intensity of implemented interventions could partly explain these results. Strong cross-sectional associations supported the theoretical framework used. Further research is warranted to determine the effectiveness of interventions targeting both adverse physical and psychosocial work factors in preventing WMSP.

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List of tables

Table 1. Characteristics of the study population before (T1) and after (T2) QHES implementation……….51 Table 2. Frequency and proportion of participants who reported being exposed to interventions in the two QHES areas of interest at T2………52 Table 3. Prevalence and prevalence ratios (PR) of adverse physical and psychosocial work factors before (T1) and after (T2) QHES implementation, by sex………53 Table 4. Prevalence and prevalence ratios (PR) of adverse physical work factors according to participants’ self-reported exposure to interventions in the Workplace environment area after QHES implementation (T2), amongst all participants and by sex………...….55 Table 5. Prevalence and prevalence ratios (PR) of adverse psychosocial work factors according to participants’ self-reported exposure to interventions in the Management practices area after QHES implementation (T2), amongst all participants and by sex………..56 Table 6. Prevalence and prevalence ratios (PR) of work-related musculoskeletal problems (WMSP) according to participants’ self-reported exposure to interventions in both the Workplace environment and Management

practices areas simultaneously, after QHES implementation (T2), amongst all participants and by sex………57

Table 7. Exploratory analyses at T2 to determine the association between the prevalence of WMSP of any region and adverse physical work factors, amongst all participants and by sex………..59 Table 8. Exploratory analyses at T2 to determine the association between the prevalence of WMSP of any region and adverse psychosocial work factors, amongst all participants and by sex……….60 Table 9. Exploratory analyses at T2 to determine the association between the prevalence of WMSP of any region and combined exposure to at least one adverse physical work factor and at least one adverse psychosocial work factor, amongst all participants and by sex………..61 Table 10. Exploratory analyses at T2 to determine the association between the prevalence of WMSP of any region and psychological distress, amongst all participants and by sex………...62 Table 11. Exploratory analyses at T2 to determine the association between the prevalence of WMSP of any region and combined exposure to at least one adverse physical work factor, at least one adverse psychosocial work factor and high psychological distress, amongst all participants and by sex………..63 Table S1. Prevalence and prevalence ratios (PR) of adverse physical work factors before (T1) and after (T2) QHES implementation, amongst all participants and by sex………..97 Table S2. Prevalence and prevalence ratios (PR) of adverse psychosocial work factors before (T1) and after (T2) QHES implementation, amongst all participants and by sex………..99 Table S3. Prevalence and prevalence ratios (PR) of work-related musculoskeletal problems (WMSP) before (T1) and after (T2) QHES implementation in the subsample of participants from the two organizations that assessed WMSP at both T1 and T2, amongst all participants of this subsample and by sex……….101

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Table S4. Prevalence and prevalence ratios (PR) of adverse physical work factors according to participants’ self-reported exposure to interventions in the Workplace environment area after QHES implementation (T2), amongst all participants and by sex………..103 Table S5. Prevalence and prevalence ratios (PR) of adverse psychosocial work factors according to participants’ self-reported exposure to interventions in the Management practices area after QHES implementation (T2), amongst all participants and by sex………105 Table S6. Prevalence and prevalence ratios (PR) of work-related musculoskeletal problems (WMSP) according to participants’ self-reported exposure to interventions in both the Workplace environment and

Management practices areas simultaneously after QHES implementation (T2), amongst all participants and by

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List of figures

Figure 1. Theoretical framework for the development and maintenance of work-related musculoskeletal problems (WMSP) ………...11

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List of abbreviations and acronyms

CI Confidence interval

BNQ Bureau de Normalisation du Québec

EQCOTESST Québec Survey on Working, Employment and Occupational Health and Safety Conditions ERI Effort-reward imbalance

INSPQ Institut national de santé publique du Québec

PR Prevalence ratio

QHES Québec Healthy Enterprise Standard WMSP Work-related musculoskeletal problems

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Acknowledgements

I’d like to thank my research supervisor Dr. Chantal Brisson for her support throughout the various steps of this project. Your work, scientific rigour and intellect are admirable and I am grateful to have had the opportunity to work with you on a project of great interest to me. I also wish to thank you for welcoming me into your research team and for your confidence in my ability to contribute as a member of that team so early in my career. The experience I acquired during this time has been an invaluable asset to both my graduate and professional training and has provided me with the necessary financial support to continue my studies.

I’d also like to extend my sincerest thanks to Caroline Duchaine, coordinator of Dr. Brisson’s research team, for her continuous scientific and moral support these past two years. You have been an integral part of my graduate experience and I am grateful to have had you next door or at my fingertips throughout this process. In great part, this project and all its associated publications and communications were made possible thanks to you. I also owe thanks to all of Dr. Brisson’s research team for their varying types of support, especially Manon Levesque, Mahée Gilbert-Ouimet and Xavier Trudel. You have all contributed to my professional training in one way or another and I thank you for that.

I would also like to thank my research co-supervisor Dr. Clermont E. Dionne whose support has taken a number of forms over the course of this project. Thank you, especially, for answering my impromptu questions and for having the confidence in me to carry out this project.

Thank you to Pierre-Hugues Carmichael for your help during data analysis and to Ginette Desbiens for your help with all the logistical technicalities inherent in this line of work and your ability to make these simple. I’d also like to thank Gisèle Groleau for her invaluable academic help and advice these past two years.

I also owe thanks to La Fondation du CHU de Québec for awarding me the bursary Bourse de formation

Desjardins pour la recherche et l’innovation. This award offered me financial support during my studies.

I’d also like to thank my friends and family for their support and understanding, particularly Kerstin Wenzel. The physical distance that separates us never hindered our emotional connection and I am grateful for that. Finally, I extend a very special thanks to the friend and family I chose, Jesse MacPherson, without whom this project would not have been possible.

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Foreword

This master’s thesis includes an inserted manuscript for the article titled “Impact of the Québec Healthy Enterprise Standard on adverse physical and psychosocial work factors and work-related musculoskeletal problems”. This article was submitted for publication in the peer-reviewed journal Scandinavian Journal of

Work, Environment & Health. In order to avoid redundancy, only one reference list (situated after the last

chapter) was created for this master’s thesis. Moreover, results were simplified to one model in the article tables. More detailed tables and results will be provided in the Supplementary materials for publication; these are presented together in Appendix F.

I am the first author of this inserted manuscript. I wrote the research protocol for this master’s project and conducted a literature review on this topic. I presented the results of my structured literature review regarding the effectiveness of organizational psychosocial interventions in reducing musculoskeletal problems at the 85th Conference of the Association francophone pour le savoir in an oral communication. Although data was collected by the Institut national de santé publique du Québec (INSPQ), I planned and carried out the statistical analyses and interpreted the results. The data used in this project were collected as part of a larger project conducted by the INSPQ to assess the impact of the QHES on various occupational risk factors and health outcomes. Several of the co-authors of this manuscript were responsible for this larger project including Michel Vézina (INSPQ), Marie-Michèle Mantha-Bélisle (INSPQ), Hélène Sultan-Taïeb (Department of organization and human resources, University of Québec in Montreal), France St-Hilaire (Management School, University of Sherbrooke) and my research supervisor Chantal Brisson (Faculty of medicine, Laval University). All co-authors provided their feedback regarding the inserted manuscript. Of note, their comments in both emails and during in-person meetings have been a valuable source of information regarding the technicalities of the QHES and have allowed me to better situate and understand my contribution to this larger project. The results of this inserted manuscript have been communicated to decision-makers, knowledge users and researchers at the Canadian Institute for the Relief of Pain and Disability conference Safe, Healthy and

Productive Workplaces: Learning from research and practice in Vancouver (oral and poster communications)

as well as Les journées da la recherche CHU de Québec-Université Laval in Québec (oral communication). They will also be presented at the 32nd_{International Congress on Occupational Health in Dublin Ireland.}

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Introduction

In Canada, musculoskeletal disorders are amongst the most costly and most frequent health problems experienced by the working population (Public Health Agency of Canada, 2013). Work-related musculoskeletal problems (WMSP) represent an important subset of these disorders and constitute a group of painful, non-traumatic inflammatory lesions manifested by chronic pain and functional limitations (Vézina et al., 2011). In Québec, it is estimated that over one-fifth of workers suffered from a WMSP between 2007 and 2008 (Vézina et al., 2011) and WMSP represent almost 40% of compensated days for all occupational injuries (Michel et al., 2010). Efforts to reduce the public health burden associated with this frequent, costly and disabling health problem are important.

The interaction of multiple factors can contribute to the development and maintenance of WMSP, including adverse physical and psychosocial work factors (Stock, Nicolakakis, Messing, Turcot, & Raiq, 2013). These occupational risk factors for WMSP are modifiable and the implementation of preventive, organizational-level interventions targeting both the physical and psychosocial work environments could potentially reduce these harmful occupational exposures and thus reduce the prevalence of WMSP. In 2008, the Bureau de Normalisation du Québec (BNQ) developed the standard “Prevention, Promotion and Organizational Practices

for Health in the Workplace” (BNQ9700-800/2008). Commonly called the Québec Healthy Enterprise Standard

(QHES), this standard assists companies in creating organizational interventions tailored to their occupational context by addressing four areas of activity known to have an impact on workers’ health: Lifestyle habits,

Work-life balance, Workplace environment and Management practices (Bureau de Normalisation du Québec,

2008b). Interventions implemented in these latter two areas aim to improve, respectively, the physical and psychosocial working conditions of workers. If these interventions are effective in reducing adverse physical and psychosocial work factors, they may potentially improve workers’ musculoskeletal health.

Several Québec organizations have since adopted the QHES and implemented interventions in the context of this standard. However, the impact of these interventions on workers’ musculoskeletal health outcomes or on their occupational exposure to adverse physical and psychosocial work factors has not yet been evaluated. The evaluation of interventions related to this standard is essential to assess its impact. Moreover, few interventions targeting both the physical and psychosocial work environments to reduce WMSP have been evaluated and, to the author’s knowledge, none in the context of an occupational health standard. Further, only two studies (Gilbert-Ouimet et al., 2011; La Rosa-Rodriguez et al., 2013) have evaluated the impact of an organizational psychosocial intervention on WMSP, highlighting a considerable gap in the literature. The aim of this project was to assess the impact of organizational interventions implemented in the context of the QHES on the prevalence of adverse physical and psychosocial work factors and of WMSP.

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Chapter 1: State of knowledge

Work-related musculoskeletal problems: Context and pertinence

Musculoskeletal problems constitute a constellation of painful, non-traumatic inflammatory or degenerative lesions that can occur in several body parts, notably in the back, neck, upper extremities and lower extremities (Stock et al., 2014; Vézina et al., 2011). These problems develop gradually and can affect various musculoskeletal structures such as the bones, nerves, muscles, tendons, ligaments, joints, cartilages and intervertebral discs (da Costa & Vieira, 2010; Michel et al., 2010). Those affected report chronic pain and functional limitations (Michel et al., 2010; Vézina et al., 2011). Musculoskeletal problems typically result from an accumulation of damage that exceeds the structures’ adaptive capacity. Symptoms that originate from a single event or injury, a car crash or a fall for example, are not considered a musculoskeletal problem, but rather a traumatic injury (Michel et al., 2010).

In Canada, musculoskeletal disorders are amongst the most costly and most frequent health problems experienced by the working population (Public Health Agency of Canada, 2013; Stock et al., 2014). In 2008, the Public Health Agency of Canada estimated the direct and indirect costs of musculoskeletal disorders in Canada to be $7.2 billion CAD (Public Health Agency of Canada, 2013). The Québec Survey on Working,

Employment and Occupational Health and Safety Conditions (EQCOTESST) showed that over 62.9% of a

representative sample of the Québec workforce in 2007-2008, suffered from musculoskeletal pain that disrupted their daily activities at least occasionally in the past year (Vézina et al., 2011). As one of the main reasons for work leaves and absences (Chartered Institute of Personnel and Development, 2015; Stock et al., 2014), musculoskeletal problems are an important source of loss of productivity costs for employers and burden our national economy with medical costs and salary compensations.

Unfortunately, it is unlikely that this burden be alleviated soon (Woolf & Pfleger, 2003). In the United States (US), an industrialized country sharing many similarities with Canada, the number and percentage of American adults reporting a disability due to musculoskeletal problems has steadily been increasing since 1991 and these problems constitute the most common cause of disability amongst both men and women (Theis, Hootman, Helmick, & Brault, 2010), with annual costs estimated at above $50 billion USD (daCosta, Baptista, & Vaz, 2015). In comparison, cardiovascular diseases, the second most common cause of disability in the US, has decreased during this same period (Theis et al., 2010). In fact, while six out of 10 of the most common causes of disability in the US have either decreased or remained stable between 1991 and 2005, musculoskeletal problems have increased (Theis et al., 2010). Moreover, the prevalence and risk for musculoskeletal problems increases with age (daCosta et al., 2015) and is associated to lifestyle factors such as obesity and lack of physical activity (da Costa & Vieira, 2010; Woolf & Pfleger, 2003). Given the reality that

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the Canadian population is aging (Statistics Canada, 2016) and that these lifestyle factors are increasingly more common (Finucane et al., 2011; Hallal et al., 2012), the prevalence of musculoskeletal problems is likely to continue increasing.

The causes of musculoskeletal problems are varied and complex. Worldwide, 37% of low back pain, the most common musculoskeletal problem (Woolf & Pfleger, 2003), can be attributed to paid employment (Punnett et al., 2005). Work-related musculoskeletal problems (WMSP) thus represent an important subset of musculoskeletal disorders. These are conceptualized as non-traumatic, significant musculoskeletal pain experienced often or chronically, disrupting the daily activities of the person affected, and perceived as partially or completely related to the person’s employment (Vézina et al., 2011). Occasional pain and accident-related symptoms are not included in this conceptualization. Using this definition, 20.5% of employees surveyed by the aforementioned EQCOTESST suffered from a WMSP between 2007 and 2008 and significantly more women than men reported a WMSP (Vézina et al., 2011). In a subsample of non-management employees, 22% of those suffering from a WMSP missed at least one workday in the past year, with a mean absence of 25 days (Stock et al., 2014). In Québec, one in three compensation claims filed for all occupational injuries are for a WMSP and the accumulated compensation days for WMSP accepted between 1998 and 2007 averaged at almost 2.5 million days annually, representing 37.8% of compensated days for all occupational injuries (Michel et al., 2010). It is noteworthy to mention that, in Québec, compensation claims for WMSP are often underreported (Stock et al., 2014); the prevalence and economic impact of WMSP may therefore be under-estimated.

WMSP thus constitute a major public health concern and efforts to reduce the human and economic burdens associated with this frequent, costly, and disabling health problem are important.

The role of work factors in the etiology of WMSP

The interaction of multiple factors can contribute to the development and maintenance of WMSP. Indeed, the multifactorial origin of WMSP has been confirmed by researchers in countless studies and several systematic reviews and meta-analyses (da Costa & Vieira, 2010; McLean, May, Klaber-Moffett, Sharp, & Gardiner, 2010; Sundelin et al., 2015). The importance of workplace factors in the etiology of musculoskeletal problems is highlighted in these reviews; WMSP can be caused by and/or exacerbated by certain work factors (Michel et al., 2010). According to the literature, these occupational exposures originate from two main sources: the physical work environment, including the biomechanical factors involved in performing certain occupations, and the psychosocial work environment. Given the sheer vastness of the published literature examining the association between work factors and musculoskeletal health (Bernard et al., 1997; Punnett, 2014), the aim here is to synthesize the results from several systematic reviews and meta-analyses that addressed this topic.

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It is important to mention that, historically, many researchers found associations between work factors (both physical and psychosocial) and musculoskeletal problems and thus argued that these factors were potential antecedents to WMSP (Lang, Ochsmann, Kraus, & Lang, 2012). However, the early literature on this topic generally relied on cross-sectional data and contained important methodological limitations (Punnett, 2014). Longitudinal designs are necessary to support such hypotheses and in order to determine the causal plausibility of work factors in the etiology of musculoskeletal problems. Additionally, several reviews have focused on a single musculoskeletal structure as a health outcome, such as the neck or lower back, rather than the ensemble of regions that can constitute a WMSP. As such, reviews conducted within the past decade, that included studies with longitudinal designs, or that did not restrict their musculoskeletal health outcome to one region will be given greater import in the present synthesis.

Physical work factors

In the context of workplace risk factors for the development and maintenance of WMSP, physical work factors refer to both the biomechanical factors involved in performing certain occupations (such as lifting heavy loads or exerting physical effort) and the physical work environment itself (such as workspace and equipment ergonomics). Additionally, it is important to consider that different occupational groups differ in their exposure to certain physical work factors. For example, blue collar workers are likely to be exposed to biomechanical factors unique to their respective occupations, such as overhead working for service technicians in the telecommunications sector (Crawford, Lalou, Spurgeon, & McMillan, 2008). In contrast, physical factors such as desk ergonomics are more pertinent for typically white-collar occupational groups such as office workers. In the EQCOTESST, while 7.3% of white collar workers reported being exposed to four or more adverse physical work factors, that prevalence jumped to almost 50% amongst blue collar workers (Vézina et al., 2011). As such, physical occupational exposures relevant to each occupational group will be examined separately in this narrative literature review.

Regarding blue collar workers’ occupational exposures, a series of systematic reviews were conducted in order to investigate the role of physical work factors in the etiology of low back pain using the Bradford-Hill criteria of causality (Roffey, Wai, Bishop, Kwon, & Dagenais, 2010a; Wai, Roffey, Bishop, Kwon, & Dagenais, 2010a, 2010b, 2010c). Concerning occupational carrying, a review of nine high quality prospective and case-control studies revealed that there was no strong or consistent evidence for the association between low back pain and occupational carrying (Wai et al., 2010b). The same conclusion was made for occupational pushing or pulling based on 13 primary studies (Roffey et al., 2010a). The evidence regarding occupational bending or twisting was conflicting and the authors concluded that certain subcategories of occupational bending or twisting could contribute to low back pain (Wai et al., 2010a). Regarding occupational lifting, there was moderate evidence found for the association between certain types of lifting and the occurrence of low back

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pain, the association being more consistent for heavy lifting (25-35kg); but none of the 35 studies identified met the Bradford-Hill criteria of causality (Wai et al., 2010c). These authors conclude each of their reviews with a statement that it is unlikely that the occupational exposures assessed (occupational carrying, pushing or pulling, bending and twisting or lifting) were independently causative of low back pain in the working populations studied (Roffey et al., 2010a; Wai et al., 2010a, 2010b, 2010c).

These results contradict the results of another systematic review published in that same year addressing WMSP of any region, rather than specifically low back pain. Da Costa and Vieira (2010) reviewed 63 high-quality, longitudinal studies and found that the most common biomechanical risk factors with at least reasonable evidence of a causal relationship for the development of WMSP of any region were excessive repetition, awkward postures, heavy physical work, and heavy lifting. Similarly, in a report published by the National Institute for Occupational Safety and Health, the authors found moderate to strong evidence of an association between musculoskeletal disorders and certain work-related physical factors, namely posture, repetitive movements, exposure to whole body vibrations, and lifting or forceful movements (Bernard et al., 1997).

In light of the relatively common inconclusive results generated by systematic reviews examining the association between physical work conditions and musculoskeletal problems (Lundberg, 2015), the Swedish Government recently tasked a research group to conduct a systematic review of longitudinal studies examining back pain and all risk factors associated with the work environment (Sundelin et al., 2015). One hundred and nine studies were identified encompassing a large variety of occupational groups mainly from Europe and North America. Contrary to the findings published in Spine Journal, the authors found moderate to strong evidence for an association between a high prevalence of back pain and occupations with physically demanding work tasks such as lifting, manual handling, non-neutral postures (when the back is bent or twisted), kneeling and squatting postures, and exposure to whole body vibrations (Sundelin et al., 2015). For traditionally white collar occupational groups, a team of researchers in Thailand conducted two systematic reviews of longitudinal studies published between 1980 and 2011 exploring the risk factors for the development of non-specific neck pain and low back pain amongst office workers (Janwantanakul, Sitthipornvorakul, & Paksaichol, 2012; Paksaichol, Janwantanakul, Purepong, Pensri, & van der Beek, 2012). Regarding the onset of neck pain, only individual risk factors had strong predictive evidence, such as previous history of neck complaints and being a woman. Keyboard placement and irregular head and body posture were physical risk factors with limited positive evidence (Paksaichol et al., 2012). Regarding the onset of low back pain in office workers, the authors concluded that there is limited evidence that postural risk factors are associated with the development of low back pain. Moreover, there is limited evidence proposing that

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workspace-related ergonomics is not predictive of the onset of low back pain, such as adjustability of chair and desk, armrests, screen height, and disturbance from glares or reflection (Janwantanakul et al., 2012).

In parallel, the authors of another systematic review found only limited evidence for the causal relationship of computer work on the development of diagnosed neck and wrist disorders (Waersted, Hanvold, & Veiersted, 2010). This review focused on the association between physical work factors specific to computer work and physician-diagnosed musculoskeletal disorders of the neck and upper extremities. The authors found insufficient evidence for the majority of the physical risk factors studied and found no moderate or strong evidence of a causal relationship (Waersted et al., 2010). An aspect of computer work and traditional white collar occupations not included in the above review is that of sitting. According to a systematic review using the Bradford-Hill criteria of causality, there is strong and consistent evidence that there is no association between occupational sitting and low back pain (Roffey, Wai, Bishop, Kwon, & Dagenais, 2010b).

Psychosocial work factors

The psychosocial work environment refers to all organizational and interpersonal conditions of a workplace (Sauter & Moon, 1996), for example the level of control a worker has on decisions that affect them or the quality of support they receive from superiors. The psychosocial work environment is therefore an important source of occupational stress; the latter being an important health determinant (Johnson & Hall, 1988; Karasek, 1979; Siegrist, 1996). Adverse psychosocial work factors are conceptualized as the organizational and interpersonal factors of a workplace that may negatively impact workers’ mental and/or physical health. The predominant psychosocial work factors identified in the scientific literature reflect the components of two internationally recognized models for conceptualizing and operationalizing psychosocial work factors: Karasek’s demand-control-support model (Karasek, 1979) and Siegrist’s effort-reward imbalance model (Siegrist, 1996). In his model, Karasek (1979) postulates that workers experiencing both high psychological job demands (i.e., excessive workloads, time constraints, conflicting demands) and a low control to respond to those demands, a state known as “job strain”, are more likely to develop negative health outcomes. In addition, low social support at work can independently affect adverse health outcomes as well as amplify the effect of job strain on a health outcome (Johnson & Hall, 1988). According to Siegrist (1996), high extrinsic efforts, similar to Karasek’s psychological demands, should be rewarded in at least one of three ways: income, esteem (approval and recognition), and status control (promotion prospects and job security). Siegrist postulates that a continued occupational imbalance between high effort and low reward, called “effort-reward imbalance”, is particularly stressful to workers and may negatively affect their health (Siegrist, 1996).

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Several systematic reviews of longitudinal studies have been conducted in an effort to determine the predictive value of adverse psychosocial work factors on the onset of non-specific and region-specific WMSP. One of the most recent and comprehensive efforts to achieve this was undertaken by Lang and colleagues in 2012. They conducted a systematic review and meta-analysis of 50 stability-controlled prospective longitudinal studies assessing the lagged effect of adverse psychosocial work factors in the development of WMSP in industrialized work settings published until 2009 (Lang et al., 2012). All effect size information was extracted and converted to odds ratios (OR) which were then pooled for each factor-musculoskeletal region relationship. Twenty-three of the 45 possible relationships had at least five effect sizes available and, of these, 17 provided statistically significant and positive pooled OR estimates ranging from 1.15 to 1.66, the highest being an estimate for the relationship between highly monotonous work and low back pain. Most of the adverse psychosocial work factors studied had small but significant lagged effects on the development of WMSP. The most consistent adverse psychosocial work factors identified by this review (and therefore affecting all regions studied: lower back, neck and/or shoulder, upper extremity and low extremity symptoms) were low job control, low social support at work, and highly monotonous work. High psychological job demands also had a significant association with the onset of musculoskeletal problems for all regions except the lower extremities. The development of lower back and neck and/or shoulder symptoms was also associated with exposure to job strain. Longitudinal studies that adequately control for the stability of an outcome, such as existing musculoskeletal problems at baseline, can provide pertinent evidence to address the question of causality (Lang et al., 2012). Lang and colleagues’ (2012) meta-analysis thus provides support for the causal impact of adverse psychosocial work factors in the development of WMSP.

Likewise, other systematic reviews (Kraatz, Lang, Kraus, Munster, & Ochsmann, 2013) and meta-analyses (Hauke, Flintrop, Brun, & Rugulies, 2011) of longitudinal studies revealed similar results to support this causal relationship, though they did not control for the stability of WMSP. Controlling for the physical risk factors for WMSP, Kraatz and colleagues (2013) found a strong level of evidence for the incremental effect of high psychological demands, job strain, and low social support at work, particularly from co-workers, in the development of neck and shoulder disorders in workers. Considering all body regions and psychosocial work factors, 33 of the 54 longitudinal studies identified by Hauke and colleagues (2011) found at least one statistically significant effect of adverse psychosocial work factors on the onset of WMSP. From this review, the authors also conducted a meta-analysis and found that the onset of WMSP was associated with: low social support at work, high psychological job demands, low job control, low decisional authority, low job satisfaction, and job strain. According to this meta-analysis, the risk of developing a WMSP in any body region, but particularly the lower back, was 15-59% higher among employees exposed to these adverse psychosocial working conditions (Hauke et al., 2011).

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It is evident from reviewing the literature that Karasek’s demand-control-support model is the most commonly used model to assess psychosocial work factors in the WMSP literature. However, while this model emphasizes the task-level features of an occupation, Siegrist’s effort-reward imbalance model takes into account the impact of the global economy on labour markets by focusing on broader socioeconomic conditions related to reward potential, such as income, promotion prospects and job security (Koch, Schablon, Latza, & Nienhaus, 2014). As such, it is a pertinent model to both conceptualize and operationalize psychosocial work factors. To the present author’s knowledge, only one systematic review (Koch et al., 2014) specifically examined the association between effort-reward imbalance and WMSP. In this review, 13 of the 19 studies identified, the majority of which were cross-sectional in design, found a positive and significant association between effort-reward imbalance and musculoskeletal pain and the association was thus inferred as having a moderate level of evidence (Koch et al., 2014). However, more longitudinal studies are needed in order to determine the causal role of effort-reward imbalance in the development of WMSP.

Summary: The role of adverse physical and psychosocial work factors in the

etiology of WMSP

Regarding the physical and biomechanical work factors associated with traditionally blue collar work, there is moderate to strong evidence that occupational lifting (Bernard et al., 1997; da Costa & Vieira, 2010; Wai et al., 2010c), repetitive work and movements (Bernard et al., 1997; da Costa & Vieira, 2010) and non-neutral or awkward postures (Bernard et al., 1997; da Costa & Vieira, 2010; Sundelin et al., 2015) are associated with the development of WMSP, especially in bodily regions above the waist. However, some state that it is unlikely that exposure to just one biomechanical or physical work factor can independently lead to the development of a WMSP (Roffey et al., 2010a; Wai et al., 2010a, 2010b, 2010c).

For white collar workers, the effect of physical work factors, namely workspace ergonomics, in the development of WMSP appears inconclusive; with only limited evidence to support the proposed causal association (Crawford et al., 2008; Janwantanakul et al., 2012; Paksaichol et al., 2012; Waersted et al., 2010), some limited evidence that these physical work factors have no predictive value on the onset of neck pain (Janwantanakul et al., 2012) and some strong evidence that one of these factors, sitting, has no association with low back pain (Roffey et al., 2010b).

Regarding the psychosocial work environment for all occupation types, several systematic reviews and meta-analyses of longitudinal studies demonstrate the etiological role of adverse psychosocial work factors in the development of WMSP (da Costa & Vieira, 2010; Hauke et al., 2011; Kraatz et al., 2013; Lang et al., 2012; McLean et al., 2010; Sundelin et al., 2015), with the most consistent factors being high psychological job

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demands, low social support at work, job strain, and low job control. There is also a moderate amount of evidence to suggest that effort-reward imbalance is associated with WMSP (Koch et al., 2014).

In considering the work factors involved in the etiology of WMSP, this brief narrative review of reviews highlights that a combination of multiple adverse physical work factors are important to consider amongst blue collar workers and that adverse psychosocial work factors are more consistently predictive of later WMSP and transcend occupational types.

Theoretical framework

In speculating about the underlying pathways that contribute to the development of WMSP, Stock and colleagues (2013) proposed a comprehensive theoretical framework that takes into consideration the complex relationships between the organizational work environment, psychosocial work factors, physical work factors, individual factors, psychological distress and WMSP (see Figure 1 for a visual representation of this model, re-created by the present student).

The organizational work environment encompasses a number of work features such as the company culture, management practices, job training, and the organization of health and safety at work (Stock et al., 2013). In addition, it also refers to all aspects of the work organization such as work schedules and flexibility, type of employment (self-employed, contract, salaried), methods of remuneration, benefits and absence management as well as the more technical features of work such as the workspace itself, the equipment used and the safety measures in place to protect workers’ health. The organizational work environment is thus the larger context within which the physical and psychosocial work environments exist and these various aspects of the organizational work environment can therefore have an impact on the physical and psychosocial work factors detailed previously (Stock et al., 2013).

The authors of this framework posit that the physical and biomechanical factors of work can impact the physical strain on muscles and tendons and therefore directly influence the development of a WMSP; a risk that increases with the intensity, duration and frequency of exposure to these factors (Stock et al., 2013). The role of psychosocial work factors in this etiological model of WMSP is slightly more complex. First, certain psychosocial work factors, such as job control and work demands, can moderate the impact of physical work factors on physiological strain (Stock et al., 2013). For example, possessing the decisional authority to control one’s work rhythm may lessen the impact of physically demanding tasks on the body and therefore attenuate the relationship between physical work factors and WMSP. Second, adverse psychosocial work factors can increase psychological strain which, in turn, influences musculoskeletal outcomes by increasing muscle tensions and activating other neuroendocrine and autonomic processes that can impact physiological strain

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(Stock et al., 2013). Chronic exposure to these adverse psychosocial work factors may lead to prolonged muscle tension, thus contributing to both the development and maintenance of WMSP (Sauter & Moon, 1996). Third, adverse psychosocial work factors may cause increased psychological strain which could lead to the development of psychological distress or a mental health problem (Stock et al., 2013). Stock and colleagues (2013) posit that there is a bidirectional relationship between psychological distress and WMSP; psychological distress can contribute to the development of WMSP and the symptoms that characterise a WMSP could lead to psychological distress (Stock et al., 2013).

Lastly, individual factors can contribute to the risk of a WMSP independent of work exposures and could also moderate any of the aforementioned pathways in the development of a WMSP (Stock et al., 2013). These factors can include, but are not limited to, age, gender, previous injury, one’s personal beliefs, motivation, co-morbidities, and overall fitness.

According to Stock’s theoretical model of WMSP, interventions that aim to improve the organizational work environment and, more specifically, the physical and psychosocial work factors within this environment, could potentially decrease not only the workers’ risk of developing a WMSP but also the risk of an existing WMSP from becoming chronic. This theoretical framework relies on two pathways of change to improve WMSP. Interventions targeting the adverse physical and psychosocial work factors will: 1) lead to reductions in the occupational physical and biomechanical risk factors for WMSP and 2) lead to reductions in the occupational psychosocial risk factors for WMSP.

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Figure 1. Theoretical framework for the development and maintenance of work-related musculoskeletal problems (WMSP)

Adapted from (Stock et al., 2013)

Organizational environment Physical and/or biomechanical work factors Psychosocial work factors Physiological strain WMSP

Psychological strain Psychological distress

Individual factors can modulate any or all of these associations

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Literature review: Effectiveness of organizational interventions in

the prevention of WMSP

Concepts and sectors of activity

As reviewed above, a substantial body of evidence has emerged in the past decades emphasizing the importance of a number of workplace factors that contribute to the development and maintenance of WMSP. An overview of these work factors highlights their modifiable nature. The implementation of preventive workplace interventions targeting these occupational exposures could potentially reduce the prevalence and incidence of WMSP. Moreover, the World Health Organization has identified preventive workplace interventions as a relevant and pertinent setting for actions to improve the health of the population (Burton, 2010).

Preventive workplace interventions generally consist of a group of activities and changes implemented in the workplace to reduce employees’ exposures to adverse work factors that could contribute to adverse health outcomes, such as WMSP (Cole, Van Eerd, Bigelow, & Rivilis, 2006). These preventive efforts are thus considered primary interventions. This is in contrast to secondary and tertiary interventions which are generally curative in nature, such as screening tests and rehabilitation services for people already suffering from a WMSP (Cole et al., 2006).

Further, preventive workplace interventions can typically be categorized into individual-level and organizational-level interventions (Bongers, Ijmker, van den Heuvel, & Blatter, 2006; Egan et al., 2007), hereafter referred to as simply “organizational interventions”. Regarding interventions targeting adverse psychosocial work factors for example; whereas individual-level interventions will aim to equip employees with stress-coping techniques, organizational interventions will aim to change and improve the psychosocial work environment itself (Bongers et al., 2006; Egan et al., 2007). Given that organizational interventions specifically target the cause of the unhealthy work environment, these types of preventive interventions are hypothesized to be more effective in influencing health outcomes associated with adverse work factors (Karasek, 1979) and are likely to have a more diverse effect than individual-level interventions (Semmer, 2006). In fact, while individual-level interventions may lead to beneficial impacts on individual-level outcomes, organizational interventions have favourable impacts on both individual and collective outcomes (Lamontagne, Keegel, Louie, Ostry, & Landsbergis, 2007). Organizational interventions are thus consistent with public health priorities to improve the collective health of the population.

Adapted from a recent systematic review (Montano, Hoven, & Siegrist, 2014) and in order to better reflect the theoretical model used in this project (Stock et al., 2013), preventive organizational intervention activities can be classified into two broad categories: physical and work structure. Physical interventions target a variety of

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biomechanical and physical risk factors related to performing work tasks. Intervention activities in this category can include changes in ergonomics or equipment used and formal training in safety procedures. In contrast, the work structure category refers to the processes and procedures inherent in performing occupational tasks including the psychosocial working conditions as well as work-time related conditions. Intervention activities in this category thus center on reducing adverse psychosocial work factors by targeting work organization processes such as team organization, management practices, task structure and task enrichment as well as work pace, work-rest schedules and shifts. These intervention categories are not mutually exclusive and interventions may target both categories at once (Montano et al., 2014). In fact, this is even encouraged in the WMSP intervention literature (Cole et al., 2006; Warren, 2001).

In the context of the present project, the purpose here is to review the evidence of the effectiveness of organizational workplace interventions in preventing adverse musculoskeletal outcomes in each of the following categories of intervention activities: physical, work structure, and a combination of both.

Effectiveness of physical interventions

In an effort to update the evidence regarding the effectiveness of workplace interventions in the prevention of upper extremity musculoskeletal disorders, Van Eerd and colleagues (2016) conducted a systematic review and identified 61 medium and high quality intervention evaluation studies published on this topic until 2013 (Kennedy et al., 2010; Van Eerd et al., 2016). Of the 29 intervention types identified by these authors, the majority were ergonomic and individual-level interventions. Resistance training was the only intervention type that yielded strong positive evidence in effectively preventing upper extremity musculoskeletal disorders (Van Eerd et al., 2016). Regarding organizational interventions, a moderate level of evidence was found for the effectiveness of workstation forearm supports and vibration feedback on mouse use. However, there was also a moderate level of evidence to suggest that workstation adjustment alone has no effect in preventing upper extremity musculoskeletal disorders. Moreover, other ergonomics training activities yielded mixed results on their effectiveness (Van Eerd et al., 2016). These results parallel that of another systematic review of randomized controlled trials that assessed the impact of workplace ergonomics training and/or design interventions in the prevention of upper extremity WMSP (Sim, Hoe, Kelsall, & Urquhart, 2013). However, the authors of another systematic review based on five studies did report a moderate level of evidence for chair interventions to reduce musculoskeletal symptoms among workers who sit for prolonged periods of time (van Niekerk, Louw, & Hillier, 2012).

The majority of workplace interventions to prevent WMSP are conducted in office-based workplaces (Van Eerd et al., 2016). However, several biomechanical factors are unique to those performing occupations outside the traditional white-collar work and interventions should also consider these. For example, WMSP are highly

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prevalent among health care workers and a recent systematic review found that interventions designed to prevent and reduce injuries among health care workers were generally effective (Aslam, Davis, Feldman, & Martin, 2015). The intervention activities in this review included technological interventions, educational approaches and policy changes and interventions (Aslam et al., 2015). Workers in the construction industry are also exposed to unique physical and biomechanical work factors that could contribute to a WMSP. One research group attempted to synthesize the intervention research in this industry and found that interventions were generally effective at either reducing the duration and frequency of exposure to risk factors or directly improving musculoskeletal outcomes (Rinder, Genaidy, Salem, Shell, & Karwowski, 2008). Intervention activities included modifying work techniques, improving tools and equipment and providing worker training in order to reduce workers’ biomechanical and physical exposures (Rinder et al., 2008). Amongst manufacturing workers, however, a review found inconclusive results regarding the effectiveness of interventions in reducing WMSP (Tuncel et al., 2008). These interventions included modifying the physical work elements, such as technology and work procedures, as well as improving workers’ physical capacity, typically via ergonomics training or physical exercise. However, the interventions reported in this study had a number of methodological limitations regarding intervention duration, the exclusion of important confounders, and lack of sensitivity of outcome measures. The authors highlight the need for evidence-based interventions in this sector given that some of intervention activities reviewed were based on “intuitively obvious” changes that were not actually effective (Tuncel et al., 2008).

In light of these reviews, the evidence for ergonomic interventions for office-workers appears inconclusive with only certain ergonomic components (adjustable chairs, forearm supports and mouse use feedback) being moderately effective in preventing WMSP. For more traditionally blue collar occupations, effective interventions have in common that they are tailored to the occupational context in which they are implemented and aim to directly reduce adverse physical and biomechanical exposures.

Effectiveness of work structure interventions

In contrast to physical interventions, work structure interventions typically target work-time related conditions and psychosocial working conditions. In a recent systematic review presented during a conference series (Nicolakakis et al., 2016), the authors identified three randomized control trials that increased the number of break times in a workday among office workers (two studies) and agricultural workers (one study). All three studies reported decreases in musculoskeletal pain intensity and the authors concluded the level of evidence to be moderate (Nicolakakis et al., 2016). Likewise, Van Eerd and colleagues (2016) found limited evidence in their systematic review that rest breaks are effective in preventing upper extremity musculoskeletal disorders. However, they found insufficient evidence for the effectiveness of reduced hours (Van Eerd et al., 2016). Regarding the intervention activities of task rotation and task enrichment, an older review (Bongers et al.,

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2006) identified five studies that implemented these activities in repetitive work (assembly line, cashier) or computer work (office work). However, the studies were of poor methodological quality and some inadvertently created adverse effects. The effectiveness of task rotation and task enrichment in preventing upper extremity WMSP was deemed inconclusive (Bongers et al., 2006).

To the present authors’ knowledge, no systematic review has yet been published regarding the effectiveness of organizational psychosocial interventions in preventing WMSP in the working population. As such, a structured literature review was conducted in the context of this project.

Literature review: Organizational psychosocial interventions and WMSP

Given the modifiable nature of adverse psychosocial work factors and their inherent accommodation within the greater organizational work environment, intervention efforts to target these factors should be preventive in nature and made at the organizational level to be truly effective. I conducted a structured literature review in order to identify published studies evaluating the impact of preventive organizational interventions aiming to improve the psychosocial work environment on the musculoskeletal health of workers. The methodological steps included 1) a search of the literature, 2) selection of relevant primary articles according to specified inclusion and exclusion criteria by title and abstract, 3) selection of final articles by full text review and 4) synthesis of the identified studies in a summary table.

Literature searches were conducted for peer-reviewed articles using the electronic databases PubMed, PsycINFO and Embase with no language or date restrictions. The search strategy combined four sets of keywords customized to each database, validated with two experts in the fields of psychosocial work factors (director Dr. Brisson) and musculoskeletal health (co-director Dr. Dionne) and pertaining to 1) work setting, 2) psychosocial work factors, 3) intervention, and 4) musculoskeletal health outcomes. The terms within each set were combined using the Boolean “OR” operator and the four sets were combined using the Boolean “AND” operator. Obtained references were merged into bibliography software and, after removing duplicates, 791 remained for inclusion in the present review. In addition, key references of located articles were manually retrieved if pertinent and added for review.

Criteria for the intervention element of this review were designed to be exclusive. The following definition of organizational psychosocial interventions was used: any and all modifications to the pre-existing work

organization, process and culture that aim to directly and positively influence the psychosocial work environment at an organizational-level. As such, interventions with a 1 hour or half day training sessions, on

their own, are not conceptualized as an intervention. Rather, the focus is active and committed changes in work structure and organization at an organizational level in order to prevent negative health outcomes or to promote employee health and well-being. Regarding the work element of this literature review, the only criteria

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were that study participants be current employees regardless of their work sector. Given the varied methods of operationalizing psychosocial work factors and WMSP, all psychosocial work factors and all musculoskeletal health outcomes were considered for review, regardless of the model or instrument used.

Results

Following an initial screening by title and abstract that resulted in the exclusion of 736 articles and a full text screening of 55 articles, two articles were retained that met the inclusion criteria (Gilbert-Ouimet et al., 2011; La Rosa-Rodriguez et al., 2013). The studies were conducted amongst white collar workers in the industrialized countries of France (La Rosa-Rodriguez et al., 2013) and Canada (Gilbert-Ouimet et al., 2011). Both studies did not have a control group and while one study used a prospective design (La Rosa-Rodriguez et al., 2013), the other used a repeated cross-sectional design (Gilbert-Ouimet et al., 2011). Of the two studies retained, only one study (Gilbert-Ouimet et al., 2011) observed a lower prevalence of musculoskeletal problems following the intervention.

The most recent study was a prospective study assessing the impact of an organizational intervention on the musculoskeletal and mental health of workers in a social security organization in France (La Rosa-Rodriguez et al., 2013). The intervention was initiated by the organization in an effort to combat work stress and the upper management of the company organized and implemented the intervention. The main intervention activities included supervisor training in stress management, developing better social dialogue in the context of the work structure and a commitment plan by upper management to better promote career growth and opportunities. Only 74 participants filled out the questionnaire at both baseline and at the 2-year follow-up, with only 60% of employees participating in the data collection at baseline and 45% at follow-up. Participants were mainly white collar workers with roles as general employees, technicians or supervisors. Regarding the health outcomes assessed, the intervention was not effective in reducing musculoskeletal problems, mental health problems or psychological distress (statistically non-significant decreasing trends). Moreover, there was an increase in psychological distress for managers from pre- to post-intervention. In regards to the impact of the intervention on psychosocial work factors, a statistically significant decrease in ISO-strain (a combination of high psychological demands, low job control and low social support) and a decrease in low social support from colleagues were observed (La Rosa-Rodriguez et al., 2013).

There are several limitations to this study. The small sample size, low participation rate and the 50% loss at follow-up may cause two important methodological limits: low statistical power and a high possibility of a selection bias, thereby threatening the validity of the results. Moreover, there was no control group, no confounding factors were taken into account in the analyses and the authors do not specify what instruments were used to assess musculoskeletal problems nor mental health problems. These limitations greatly impede the interpretation of the results.

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The second study identified had a repeated cross-sectional design and assessed the impact of an organizational intervention implemented in a large public organization offering insurance services (Gilbert-Ouimet et al., 2011). The intervention was designed and implemented as a conjoined effort between the research team and the organization. The intervention targeted the entire organization and was organized into three phases. In the development phase, intervention priorities were identified at the department-level with the help of researchers’ a priori risk evaluation of adverse psychosocial work factors and employee focus groups conducted by members of the research team. The implementation phase was the organization’s responsibility and the head manager of each department kept a record of all changes implemented within their department with the aim or clear consequence of improving the psychosocial work environment. For the last phase, effectiveness, qualitative and quantitative evaluations were conducted by the research team to assess intervention implementation and the possible changes in the psychosocial work environment and impact on health outcomes. These revealed that the prevalence of psychological distress and of musculoskeletal symptoms of the neck, shoulder and lower back had statistically significantly decreased from baseline to 30 months post-intervention. Moreover, the intervention proved effective in decreasing several adverse psychosocial work factors such as high psychological job demands, low co-worker social support, and low reward. However, changes in job control, supervisor support, effort-reward imbalance and job strain were statistically non-significant (Gilbert-Ouimet et al., 2011).

This study overcomes some of the limitations of the previous intervention study by La Rosa-Rodriguez and colleagues (2013), namely by having a large sample size, taking into account several confounders as well as using validated instruments. However, this study lacked a control group; a control group would have allowed the researchers to isolate the effect of the intervention on the outcome studied regardless of other factors. More importantly, an ergonomic program was implemented during the course of the organizational psychosocial intervention (Gilbert-Ouimet et al., 2011). The improvement in musculoskeletal outcomes observed in this study may therefore be at least partially due to intervention activities implemented as part of this ergonomic program. It remains that, according to Stock’s WMSP model (Stock et al., 2013) and given that this intervention was associated with important reductions in both adverse psychosocial work factors and psychological distress, it is plausible that this type of intervention is effective in reducing WMSP. However, the above limitations render the evidence inconclusive for WMSP.

Evidence does show, however, that organizational psychosocial interventions can have a positive impact on various indicators of workers’ physical and mental health (Bambra, Egan, Thomas, Petticrew, & Whitehead, 2007; Bambra et al., 2009; Egan et al., 2007). In a review of seven systematic reviews examining the health impacts of organizational psychosocial interventions, Bambra and colleagues (2009) found that organizational changes to the psychosocial work environment had generally beneficial effects on both the physical and

Evaluating the impact of organizational interventions implemented as part of the Québec Healthy Enterprise Standard on physical and psychosocial work factors and work-related musculoskeletal problems

Evaluating the impact of organizational interventions implemented as part

of the Québec Healthy Enterprise Standard on physical and psychosocial

work factors and work-related musculoskeletal problems

Mémoire

Karine Aubé

Maîtrise en santé publique

Maître ès sciences (M. Sc.)

Québec, Canada

Evaluating the impact of organizational interventions

implemented as part of the Québec Healthy Enterprise

Standard on physical and psychosocial work factors

and work-related musculoskeletal problems

Mémoire

Karine Aubé

Sous la direction de :

Chantal Brisson, directrice de recherche

Clermont Dionne, codirecteur de recherche

Résumé

Summary

Table of contents

List of tables

List of figures

List of abbreviations and acronyms

Acknowledgements

Foreword

Introduction

Chapter 1: State of knowledge

Work-related musculoskeletal problems: Context and pertinence

The role of work factors in the etiology of WMSP

Physical work factors

Psychosocial work factors

Summary: The role of adverse physical and psychosocial work factors in the

etiology of WMSP

Theoretical framework

Literature review: Effectiveness of organizational interventions in

the prevention of WMSP

Concepts and sectors of activity

Effectiveness of physical interventions

Effectiveness of work structure interventions