Workplace interventions for neck pain in workers
Abstract
This is a protocol for a Cochrane Review (Intervention). The objectives are as follows:
The objective of this review is to determine the effectiveness of workplace interventions in working age adults with neck pain.
Background
Musculoskeletal disorders (MSD) are the most common causes of long term sick‐leave and disability pension in several industrial countries. Lost days due to MSD are 42%, 40% and 33% in Norway, Sweden and United States, respectively (Nordlund 2004; Statistics Norway 2004; US Dept Labor 2004). Recurrent and chronic pain accounts for a substantial portion of worker absenteeism (Nachemson 2000; Nordlund 2004). In addition to personal consequences, such disorders represent a large economic loss for society.
Neck and shoulder pain seems to be more prominent in the general population than previously known (Lidgren 2008). A recent review showed that neck pain was common in the adult population; for the majority of studies included in the review, the12‐month prevalence was between 20% and 50% (Hogg‐Johnson 2008). In the same review, the 12‐month prevalence for neck pain with limiting activities was between 2% and 11%.
The causes for musculoskeletal disorders in general are multifactorial (Bongers 2006; Punnet 2004). This is also the case for neck and shoulder pain (Bongers 2006; Côté 2008). Physical and psychosocial work exposures have been shown to be risk factors for neck and shoulder pain for both physical (Ariens 2001; Côté 2008; van der Windt 2000) and psychosocial work exposure (Ariens 2000; Bongers 2002; Boyle 2008; van der Windt 2000). Individual factors (Linton 2000) and non‐work‐related factors may also contribute to the development of such pain (Bongers 2002; Boyle 2008). Due to this complexity, the contribution of different risk factors in the development and exacerbation of problems in the neck and shoulder may be difficult to explain.
Primary prevention is still important for highly exposed groups. However, a stronger focus on reducing the consequences of musculoskeletal disorders rather than just on preventing the onset of such disorders, may be appropriate (Frank 1996). Although there are no systematic reviews examining how the workplace affects sickness absence due to neck pain, studies have shown that the workplace does have an impact (Bergstrom 2007).
The International Classification of Functioning, Disability and Health (ICF) (WHO 2001), offers a conceptual biopsychosocial model to describe health and functioning on the body, individual and societal level. The ICF, together with the tenth version of the International Classification of Diseases (ICD‐10) make up the two core classification systems of WHO. Diseases, disorders and disabilities are included in the conceptual model of ICF (Figure 1). The classification system codifies disabilities on different health dimensions within a framework of up to 1424 codes. In the field of occupational health, ICF has been used to describe work‐related factors that influence the health of employees (Heerkens 2004) and as a measure for general practitioners to assess functioning in relation to sick leave and disablement pension (Brage 2004). ICF includes health factors that can be modified by interventions (Verbeek 2004). Multidimensional intervention strategies require the evaluation of many underlying concepts (Staal 2002). We will use the ICF as a way to describe, sort and analyse different workplace interventions into intervention groups in this review, according to whether the intervention is trying to change or modify body functions (including psychological functions), activity performance, participation challenges, environmental factors (physical‐, social‐ or attitudinal‐) or individual factors.
International Classification of functioning, disability and Health, ICF (WHO 2001). The model and definitions of the health and health‐related components in ICF
Workplace interventions may promote health, be preventative, curative or rehabilitative, depending on the aim of the intervention (to avoid, solve, reduce or compensate the problem). As there is no consensus or commonly used definition of the term 'workplace intervention', we developed one for this review: 'Workplace interventions are any action at the workplace that aims to prevent health problems, maintain participation in work, or facilitate the early return to work. The goals of these interventions are to modify the employees' body functions, their activity performance, participation challenges or the physical, social or attitudinal environment'. In this review, workplace interventions that focus on preventing health problems are not included.
Corporate social responsibilities of companies are on the agenda in many western countries. This includes the companies' responsibilities towards their own employees on sickness benefits. Accordingly, new social policies and systems highlight the "inclusive working life" and encourage a closer contact between the absent worker and the workplace. Workers who have not returned to work within two to three months are at high risk for disability and dropping out of the work arena (Frank 1996). Therefore, encouraging early return‐to‐work by intervening at the workplace may be an efficient way to reduce socioeconomic and personal consequences of musculoskeletal disorders (Elders 2004).
Therefore, we decided to focus on the workplace as an arena for interventions. On a group level, it is essential to identify which workplace‐based intervention strategies are effective in increasing participation at work and returning injured workers to work earlier, in order to 'weed out' ineffective interventions.
Objectives
The objective of this review is to determine the effectiveness of workplace interventions in working age adults with neck pain.
Methods
Criteria for considering studies for this review
Types of studies
Only randomised controlled trials (RCT) will be included. There will be no language limitations on the literature search.
Types of participants
Inclusion criteria:
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Age: Working age male and female adults (18 to 67 years)
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Working status: Workers at work or absent from work (on sick leave, early retirement or disability pension), but still connected to a workplace by employment agreements (permanent or temporary).
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Job sectors: All sectors, branches and types of jobs
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Conditions: Workers with reported neck pain of acute (less than six weeks), subacute (six to 12 weeks) or chronic (12 weeks or more) duration. Shoulder pain will only be included when it is described in conjunction with neck pain, otherwise, it will be excluded . Studies where the inclusion criteria of the intervention group include workers with more than neck pain will only be included when at least 50% of the participants have reported neck pain at baseline and the results include a separate analysis for neck pain.
Exclusion criteria:
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Neck pain due to specific pathological conditions (e.g. fractures, tumours, infections, inflammatory processes, ankylosing spondylitis).
Types of interventions
Inclusion criteria:
See Table 1
| Factors modified by workplace interventions | |||||
| ICF components | Body functions (b) | Activity performance (a) | Participation (p) | Environ‐mental factors (e) | Personal factors |
| Examples of included interventions | Work positions Variations in positions Education and advice about workplace/ working challenges Stress management and advice
| Task adjustments Changed work tasks Bio‐mechanical work technique Job rotation Micro‐breaks Graded activity programs Working methods Handling techniques Manual lifting /pushing/pulling techniques
| Graded participation at work Reduced hours Flexible working hours Lighter job Workload modifications Work durations Part‐time work Active sick leave Sick leave
| Physical Equipment: new chairs, tables, PC‐mouse, light, lifting aids. Work‐layout changes Work station design Work space changes | Lifestyle redesign (habits) Life Circle adaptation Aging adjustments |
| Social and attitudinal Being contacted by the workplaceEducational program towards leaders | |||||
| Combinations (b / a / p / e) | |||||
| Ergonomics; office ergonomics, ergonomic counselling, ergonomic workplace visits, multidisciplinary ergonomics interventions, participatory ergonomics Modified work Return to work (RTW) interventions | |||||
Setting: Both group‐based and individual interventions conducted at the workplace will be included:
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Body functions modifications (i.e. education and advice about workplace challenges, stress management and advice, correct positions, changing positions)
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Activity performance modifications (i.e. micro breaks, graded activity (only work‐task performance adjustments, not exercises), working methods, biomechanical work techniques, lifting, pushing and pulling techniques (actual changes not just advice), job rotation, task adjustments)
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Participation modifications (i.e. workload modifications, lighter work, work duration, reduced working hours, part‐time work, flexible working hours, active sick leave, sick leave)
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Physical environmental modifications (i.e. workstation design, work layout changes, new equipment (chairs, tables, light, computer mouse, keyboard, lifting aid), office design, work space changes)
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Social and attitudinal environmental modifications (i.e. communication and contact between supervisor and employee, early contact, supervisor and colleagues' abilities and attitudes, workplace culture, occupational health services, organizational changes, offer of work accommodation)
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Modification of personal factors (i.e. life cycle adaptation, lifestyle redesign, changed habits, age‐related adjustments)
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Combinations (i.e. ergonomics: office ergonomics, ergonomic counselling, ergonomic workplace visit, multidisciplinary ergonomic interventions, participatory ergonomics, modified work, return‐to‐work interventions)
We are not sure at this point exactly what workplace interventions will be identified in the literature, but we are planning these broad comparisons:
(i) workplace intervention versus no treatment,
(ii) workplace intervention versus usual care,
(ii) comparison of two or more workplace interventions.
Exclusion criteria:
Setting: Clinical and healthcare Iinterventions conducted outside the workplace are excluded.
Covered in other Cochrane Reviews:
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Exercise (also group gymnastic, fitness programs, aerobic, spinning, graded exercise program) (Kay 2005; Schonstein 2003)
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Multidisciplinary biopsychosocial rehabilitation (Karjalainen 2003)
Types of outcome measures
Primary outcomes
Trials using at least one of the following standardized outcome measures recommended by the Cochrane Back Review Group (Furlan 2009) will be included:
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Pain severity (self reported on a VAS or NSR scale)
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Global improvement (Proportion of patients recovered or improved, measured by an overall judgement of improvement or treatment effectiveness)
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Functional and disability status
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Well‐being / Quality of Life
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Work absenteeism (number of days on sick leave, proportion of individuals returning to work, employment status, disability pension and early retirement)
Harms and adverse effects will be included as reported in the included studies. The timing of outcome measures will be described according to the descriptions used in the included studies. They will be grouped as short‐term (measured closest to four weeks post‐randomisation), intermediate‐term (measured closest to six months post‐randomisation) and long‐term (measured one year or longer post‐randomisation) (Furlan 2009).
The first four outcomes will be measured and analysed separately for workers who report neck pain but remain at work; all outcomes will be measured for workers who are absent from work.
Search methods for identification of studies
The search strategies for MEDLINE and EMBASE were developed according to the Cochrane Handbook for Systematic Reviews of Interventions (Higgins 2008) and the Updated Method Guidelines for Systematic Reviews in the Cochrane Back Review Group (Furlan 2009). Searches for CINAHL and PsychINFO will be based on RCT search filters used at the Norwegian Health Services Research Centre. Searches in the other databases will be adapted as indicated from the search strategy for MEDLINE.
Electronic searches
Potential trials will be identified with computer‐aided searches in these electronic bibliographic databases:
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CENTRAL (Cochrane Central Register of Controlled trials; Appendix 1)
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MEDLINE (Appendix 2)
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EMBASE (Appendix 3)
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CINAHL (Appendix 4)
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PsychINFO (Appendix 5)
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ISI Web of Science (Appendix 6)
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OTseeker (Occupational Therapy Systematic review of Evidence) (Appendix 7)
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PEDro (The Physiotherapy Evidence database) (Appendix 8)
The intervention section of the MEDLINE search is purposely open, because of the diversity of terms used to describe workplace interventions (see Appendix 2).
Searching other resources
We will screen references cited in identified and included trials and contact experts in the field for further studies.
Data collection and analysis
Methods of this review will follow the Cochrane Handbook for Systematic Reviews of Interventions (Higgins 2008) and the Updated Method Guidelines for Systematic Reviews in the Cochrane Back Review Group (Furlan 2009).
Selection of studies
The title and abstract (if available) of all identified studies will be electronically stored in a Reference Manager file (RIS Inc.); duplicates will be removed before study selection.
We will pilot test our interpretation of the inclusion criteria on a sample of ten articles, including some considered to be definitely eligible, some definitely not eligible and some questionable. Thereby, the inclusion form will be revised. The full text of articles whose abstracts appear to meet our inclusion criteria, those for which we cannot make a decision based on the abstract, or articles for which there is no abstract will be obtained and independently screened by the same two review authors to determine if they meet our inclusion criteria. Consensus will be used to solve disagreements; if disagreements persist, a third review author will be consulted.
Data extraction and management
Two reviewer authors will independently extract the data from the included studies onto a standardized form that includes characteristics of the participants, interventions, outcomes and results. The form will be developed on the basis of experiences of others and we will pilot test it on three included articles. Consensus will be used to solve disagreements; if disagreements persists, a third review author will be consulted.
Assessment of risk of bias in included studies
The risk of bias for the included studies will be assessed using the 12 criteria recommended by the Cochrane Back Review Group (Furlan 2009; Higgins 2008, which are defined in Appendix 9. The criteria will be scored as ’yes’, ’no’ or ‘unclear’ and will be reported in the Risk of Bias table. A trial with low risk of bias will be defined as a trial that meets, at a minimum, criteria 1 (randomisation), 2 (allocation concealment), 5 (outcome assessor blinding) and any three of the other criteria.
Measures of treatment effect
The decision to pool the data will be determined by the homogeneity of the population, interventions, outcomes measures and timing of outcome measures. If these components are homogeneous and there are sufficient data, we will pool them quantitatively, using meta‐analyses. Depending on the statistical homogeneity, we will use the fixed or random effects model. If data are available, we will calculate an overall estimate of effect (relative risk or mean difference) and 95% confidence intervals for each outcome for each comparison across the studies. We will engage the services of a statistician from the Karolinska Institutet to assist us with the analysis.
We expect that most of the outcomes will be continuous (pain severity, functional status, days on sick leave). However, we also expect to find dichotomous outcome measures (return to work, employment status). For continuous outcomes, we will use mean differences; for dichotomous outcomes, we will use relative risks and 95% confidence intervals.
In addition, we will use ICF components as a conceptual framework to group interventions for possible statistical pooling (e.g. interventions to modify activity performance (task adjustments + micro breaks + work techniques) compared to interventions to modify physical environment (new equipment + work station lay‐out + lightning) See Table 1; Figure 1.
Analysis of combined treatments will be done as an addition to analysing the single interventions independently. We recognize that including combined treatments could be problematic because they might be too different to pool, but the practice field is demanding knowledge about which combinations of interventions work. Combined interventions seems to be an important prerequisite for measuring the effectiveness of interventions in a complex environment. In order to pool combined interventions, they will have to be clinically similar. For those that differ clinically, we will present the components, techniques and doses of the combined interventions in a table, so that practitioners are able to easily see them.
To judge if the difference is clinically significant or important should not just be based on statistically significant findings. Thus, we have added the five questions that should be addressed in order to determine the clinical relevance of the intervention, see Appendix 10 ( Furlan 2009 ).
Dealing with missing data
We will deal with missing data according to the recommendations in the Cochrane Handbook for Systematic Reviews of Interventions (Higgins 2008); contacting original investigators to request missing data, making explicit any assumptions of methods used to cope with missing data, performing sensitivity analysis and address the potential impact of missing data.
Data synthesis
Whether we have sufficient data to combine the results statistically or not, we will assess the overall quality of the evidence for each outcome by using an adapted GRADE approach (Furlan 2009). The quality of the evidence on a specific outcome is based on five domains: limitations of the study design, inconsistency, indirectness (inability to generalise) and imprecision (insufficient or imprecise data) of results and publication bias across all studies that measure that particular outcome.
The quality starts at high when at least two RCTs with a low risk of bias provide results for the outcome, and reduces by a level for each of the domains not met.
High quality evidence = there are consistent findings among at least 75% of RCTs with no limitations of the study design, consistent, direct and precise data and no known or suspected publication biases. Further research is unlikely to change either the estimate or our confidence in the results.
Moderate quality evidence = one of the domains is not met. Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate.
Low quality evidence = two of the domains are not met. Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate.
Very low quality evidence = three of the domains are not met. We are very uncertain about the estimate.
No evidence = no RCTs were identified that addressed this outcome
Subgroup analysis and investigation of heterogeneity
We will deal with subgroup analysis and investigation of heterogeneity according to the recommendations in the Cochrane Handbook for Systematic Reviews of Interventions (Higgins 2008). If sufficient data, subgroup analyses will be performed, taking into consideration: patient characteristics (gender and occupation), intervention aims (interventions that keep workers at work and those that return them to work), and ICF‐domains (body function, activity, participation and contextual factors).
Sensitivity analysis
Sensitivity analyses will be done to determine the impact on the results of studies with high versus low risk of bias and the presence/absence of randomisation, allocation concealment and outcome assessor blinding.
International Classification of functioning, disability and Health, ICF (WHO 2001). The model and definitions of the health and health‐related components in ICF
| Factors modified by workplace interventions | |||||
| ICF components | Body functions (b) | Activity performance (a) | Participation (p) | Environ‐mental factors (e) | Personal factors |
| Examples of included interventions | Work positions Variations in positions Education and advice about workplace/ working challenges Stress management and advice
| Task adjustments Changed work tasks Bio‐mechanical work technique Job rotation Micro‐breaks Graded activity programs Working methods Handling techniques Manual lifting /pushing/pulling techniques
| Graded participation at work Reduced hours Flexible working hours Lighter job Workload modifications Work durations Part‐time work Active sick leave Sick leave
| Physical Equipment: new chairs, tables, PC‐mouse, light, lifting aids. Work‐layout changes Work station design Work space changes | Lifestyle redesign (habits) Life Circle adaptation Aging adjustments |
| Social and attitudinal Being contacted by the workplaceEducational program towards leaders | |||||
| Combinations (b / a / p / e) | |||||
| Ergonomics; office ergonomics, ergonomic counselling, ergonomic workplace visits, multidisciplinary ergonomics interventions, participatory ergonomics Modified work Return to work (RTW) interventions | |||||
