Dutch monitor on stress and physical load: riskfactors, consequences, and preventive action

Irene L D Houtman, Anneke Goudswaard, Steven Dhondt, Maarten P van der Grinten,Vincent H Hildebrandt, Egbert G T van der Poel

AbstractObjectives—Due to recent changes in leg-islation on occupational health and safety,a national monitor on stress and physicalload was developed in The Netherlands tomonitor (a) risks and consequences ofstress and physical load at work, (b)preventive actions in companies to reducethese risks, and (c) organisational andenvironmental variables that facilitatepreventive actions.Methods—Information was gathered fromemployers, employees, and employees’representatives. The monitor was usedwith a nationally representative sample ofcompanies in industry, wholesale trade,and banking and finance, 782 companiesin total.Results and conclusions—The informationfrom the employees, aggregated at thecompany level, was not found to be corre-lated with that from the employer fromthe same companies. Although manyemployers do recognise risk factors forboth physical load and stress as a problemthey often seem to underestimate theproblem when compared with employeesor their representatives. This is particu-larly the case for psychosocial risk factors.Also, the perception of outcome meas-ures, especially employers who consideremotional exhaustion to be work related,were fewer than the employees’ repre-sentatives of the same organisation. Pre-ventive measures on physical load aremuch more popular than measuresagainst stress. It is the responsibility of theemployer to take more preventive actionof all kinds. They need to recognise riskfactors as problems and health outcomesto be related to work. Employees of largercompanies should participate with em-ployers to consider eVective measures,and more use should be made of supportat branch level. For specific preventivemeasures, specific predictors emerged.Except for measures to prevent workstress, information from employees didnot suYciently contribute to the initiationof preventive measures in the workplace.

(Occup Environ Med 1998;55:73–83)

Keywords: work stress; physical load; health conse-quences; prevention at work

Stress and musculoskeletal symptoms arereasons for disablement among two thirds of

the employees diagnosed to be disabled forwork in The Netherlands. It is generallyassumed that psychosocial risks at work arecausal to work stress and psychological over-load, whereas high physical exertion, awkwardpostures, repetitive movements, and heavyenduring static loads all lead to musculo-skeletal symptoms. Recently, there are indica-tions that psychosocial risks also contribute tothe prevalence of musculoskeletal symptoms.1 2

Information from the Netherlands Bureau ofStatistics3 indicates that especially the quantita-tive stress risks at work are continuouslyincreasing.4 Dutch employees have the highestwork pace scores in the European Union.5 6 Inthese studies, the Dutch rating on repetitivemovements is found to be relatively unfavour-able as well. Not only in The Netherlands, butin other countries as well, stress related symp-toms and musculoskeletal symptoms are themain determinants of sick leave, and healthcarecosts.7–10

In The Netherlands, the Dutch WorkingEnvironment Act (WEA) (1990) legislates onoccupational health and safety issues. Thisincludes an article which pays special attentionto psychological wellbeing in the workplace,and more detailed guidelines on physical exer-tion at work. This legislation aimed to promotepreventive action in the workplace. Due to theimplementation of the European frameworkdirective on health and safety, the WEA wasupdated in 1994. This resulted in a furtherstimulation of self regulation on occupationalhealth and safety policy and practice withincompanies, and employers and employees arefurther committed to take responsibility for theemployees’ health, safety, and wellbeing.These recent changes in legislation have

enhanced the Government’s need to monitorrisks at work, health consequences, and preven-tive action at the company level. In 1992 thegovernment made the TNO Division on Workand Health develop a monitor for stress andphysical work load. This had to be aninstrument to monitor risks for, and conse-quences of stress and physical load (the mainrisks at work in The Netherlands), as well aspreventive action taken by companies tocontrol these risks. Indicators of severalfacilitating or inhibiting factors had to beincluded in the instrument as well. Theinformation gathered with the monitor had tobe obtained at the level of the employer, theemployee, and the employees’ representative.This information should then be used to (a)provide steering information for the Ministryof Social AVairs and Employment on two

Occup Environ Med 1998;55:73–83 73

NIA TNO,Amsterdam,The NetherlandsI L D HoutmanA GoudswaardS DhondtM P van der GrintenV H Hildebrandt

Ministry of SocialAVairs andEmployment,The Hague,The NetherlandsE G T van der Poel

Correspondence to:Dr Irene Houtman, NIATNO, PO Box 75665, 1070AR Amsterdam,The Netherlands.

Accepted 8 August 1997

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important topics of their policy on occupa-tional health and safety (stress and physicalload), and (b) to feed back information tocompanies, under the assumption that employ-ers would use this information to adjust thecompany policy on stress and physical load.In 1993, the monitor was first used with

almost 800 companies in industry, wholesaletrade, and banking and financing. The presentpaper deals with the results of this first survey.In 1995 and 1996 the monitor study wasrepeated in these and the remaining branchesof industry, and will thus cover the wholeDutch work force. The objective of this paper isto report on (a) the prevalence of risks andconsequences of work stress and physical loadas identified by employers, employees, andemployee representatives; (b) the extent atwhich preventive actions are taken to controlstress and physical load, and the kind of meas-ures taken; (c) the main preventive actions inthe organisation, and the independent value ofemployee information when combined withemployer information.

MethodsTHE MONITOR

The monitor consists of two parts: (a) a struc-tured interview for employer and employees’representatives, and (b) a questionnaire foremployees.In constructing these two parts, national and

international monitoring methods were se-lected and evaluated on evidence for reliability,validity, and usability.11 An abundance of ques-tionnaires on risks and consequences on stressand physical load was found in the national andinternational literature. Many of these weretested on aspects of validity and reliability. Astriking absence was noted of validated inter-views for obtaining information from sourcesother than the employees themselves, especiallyon the topic of preventive policy and action.To be included, the questionnaire and inter-

view had to be concise and as eYcient as possi-ble, and parts of them should be related tonational and international equivalents. There-fore, a multifaceted approach was used to con-struct them.In the employee questionnaire parts of

diVerent questionnaires were combined. Tomeasure work stress, the job content question-naire (JCQ)12 was used to obtain scales for themain dimensions for work stress risks—that is,quantitative job demands (work pace), skilldiscretion, and decision authority (autonomy).Also the questions on social support wereincluded. To complement information on rela-tions at work, a scale on relations withcolleagues and supervisor from the Dutchquestionnaire on work and health (VAG) wasused.13 Finally, questions measuring decisionauthority with respect to working conditions,first tested in the Nova-Weba study wereincluded.14

To measure consequences of stress, aquestionnaire on emotional exhaustion (part ofthe Dutch MBI)15 and a 13 item questionnaireon psychosomatic complaints (VOEG) wereincluded.16–18

Risks for physical load and musculoskeletalcomplaints were measured by a short version ofthe questionnaire on musculoskeletal load andhealth complaints, validated for Dutch employ-ees (VBA).19 The VBA is partly based on thestandardised nordic questionnaires for mus-culoskeletal symptoms.20

With respect to preventive actions, theemployee had to indicate whether specificmeasures on stress or on physical load weretaken, either directed at the work situation or atthe worker. Also specific questions were askedon measures with respect to primary, second-ary, or tertiary prevention, introduced in theirdepartment in the past 12 months.For eYciency and coherence all questions

were to be answered yes or no. Scales whichwere originally constructed with four (JCQ) orseven (MBI) answers were reformulated to beanswered yes or no. As this might result in dif-ferent psychometric properties of the question-naire, aspects of validity and reliability will belooked into before conducting further analyses.With respect to the preventive measures, the

answer don’t know was added to yes or no, toillucidate whether a preventive action did nottake place, or whether the employee did notknow if a particular measure was introduced.Finally, several questions, considered rel-

evant as mediating or moderating characteris-tics, were included—that is, questions on sex,age, education, job title, tenure, and shift work.In the interview for employers and employee

representatives, questions on risks and conse-quences to health from the employee question-naire were always summarised. Firstly, employ-ers and employee representatives were asked ifthey considered that a work pace was present intheir organisation, and if they considered it tobe a problem in their organisation. It wasexplained to the employer or employee rep-resentative that a high work pace was indicatedby a lot of work, high work pace, and notenough time to finish things. So core parts ofthe employee questions used to construct aspecific scale were used to illustrate the conceptin the interview. For every risk dimension(decision authority, skill discretion, supportand relations at work, force, awkward postures,vibrations, etc) one yes or no question wasasked about the presence of the risk factor, and(if yes) a second if this risk factor wasconsidered to be a problem.With respect to thehealth consequences, a question was asked ifhealth complaints—for example, emotionalexhaustion—had been raised by the employeesin the past 12 months (yes or no). If thesecomplaints had been raised, it was asked if theywere considered to be work related (yes or no).In the case of emotional exhaustion it wasexplained to the employer or employees’representative that this was indicated by mentalexhaustion, being fatigued in the morning,burned out, felt frustrated, felt at the end ofone’s rope, all were core parts of questionsmeasuring emotional exhaustion in theemployee questionnaire. Other healthconsequences—such as psychosomatic com-plaints, musculoskeletal complaints, and gen-

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eral health complaints—were checked in theinterview in a comparable way.Questions on preventive action were directed

at the time of implementation (either in thepast 12 months, before this 12 month period,or not at all), the type of measure (generalmeasures,measures related to stress or physicalload, measures related to workers or to work),and type of prevention (primary, secondary, ortertiary). Also, some questions were directed tothe goal the employer wanted to obtain withthe preventive measures, the evaluation of themeasures, and the benefits obtained. Thesequestions were partly based on interviewsdeveloped by Draaisma et al,21 Laak andOlden,22 and Nossent and Klein Hesselink.23

With respect to structural prevention, ques-tions were asked about available professionalexpertise in the organisation, including thepresence or absence of an occupational physi-cian, a special coordinator for health and safetyissues, an ergonomist, an occupational hygien-ist, and a psychologist specialised in work (andhealth) issues.General preventive measures were consid-

ered to attract expertise within the area ofhealth and work—for example, by contractingan advice agency or research agency, by doing

a risk assessment, or by doing research at theworkplace. Research at the workplace may ormay not have been specifically directed at workstress or physical load.Measures to reduce work stress were specifi-

cally asked about, and could be courses ortraining (management training, courses di-rected at specifically managing work risks orspecifically directed at the reduction of ten-sion), task or job rotation, broadening of tasks,renewal of tasks, changing schedules, installa-tion of regular formal work meetings.Measures to reduce physical load were

specifically asked about as well—such ascourses, introduction of any apparatus toreduce heavy work, adjustment of task, jobrotation, adjustment of the work place, orfitness programmes.Finally, questions about potentially facilitat-

ing or inhibiting factors were included—suchas size and socioeconomic position of the com-pany, organisational characteristics (produc-tion structure, hierarchical levels).24 25 Also, theattitude towards occupational health and safetyin the branch of industry was assumed to influ-ence the prevention policy of individualcompanies. Therefore questions on thesetopics were included as well.

Table 1 Content of the instrument

Aspect Questionnaire Interview

Risks:Stress: Scales on each aspect Was aspect present in organisation?Quantitative job demands Was aspect a problem in organisation?Skill discretionDecision authority (within tasks)Social support/relations at workDecision authority in working conditions

Physical load: Scales on each aspect Was aspect present in organisation?Force Was aspect a problem in organisation?Dynamic loadAwkward posturesVibrations

Consequences: Scales on each aspect Were complaints on specific aspect raised in the past 12months?

Stress: Do you consider these complaints work related?Emotional exertionPsychosomatic complaints

Musculoskeletal problems: Scales on each aspect Were complaints on specific aspect raised int he past 12months?

Neck, upper back, and shoulder Do you consider these complaints work related?Lower back (lower back = 1 question)Upper extremitiesLower extremities Not in interview

General feeling of health One questionAbsenteeism Not in questionnaire Percentage last year; lower, equal, or higher than year beforeTurnover Not in questionnaire Percentage last year; lower, equal, or higher than year beforeNumber of people diagnosed disabled for work Not in questionnaire Number diagnosed disabled; diagnosisPrevention: Questions yes, no, or don’t know Questions past 12 months yes, no, before, or don’t knowStructural aspects—for example, professional expertiseGeneral measuresStress and physical loadIndividual, and work directedRehabilitation

Potential mediators or moderators Personal characteristics: Characteristics of the organisation:Sex Size of companyAge Type of social security insuranceEducation Commitment of employees in health and safetyJob title Issues:Permanent or temporary job Social economic situation of companyShift work Centralised versus decentralised production

Structure:Hierarchical levels in organisationPosition of organisation in marketEvaluation and general company policy with respect tohealth and safety issues

Branch characteristics:Activity of branch organisations with respect to health andsafety issues

Specific support for reduction of work stressSpecific support for reduction of physical load

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Table 1 provides a summary of the topics onrisks and consequences of stress and physicalload, preventive policy and actions, andfacilitating factors that were included in theemployee questionnaire and in the structuredinterview for the employer and employees’representative.

GENERAL PROCEDURE AND SAMPLING OF

COMPANIES

The field work was undertaken by the wagecontrol service. This service, part of the Minis-try of Social AVairs and Employment, con-tacted and visited the companies. The TNOperformed most analyses. The wage controlservice took care of the feedback of informationto the companies. This feedback was meant tostimulate and encourage wellbeing and healthat work, especially in the companies in whichthe situation was worst.Companies with 35 to 350 employees were

selected and asked to participate. The samplingof companies was designed to produce arepresentative sample of the national distribu-tion of company size (within the predeter-mined size range) and region in the selectedbranches of industry.Within each company a random sample of

employees was drawn: in companies with amaximum of 100 employees, 25 were randomlyselected and asked to fill in a questionnaire. Incompanies of more than 100 employees, 35employees were randomly selected and askedto fill in a questionnaire. If employers or com-panies refused to participate, another employeror company in the same branch of industry,about the same size, and in the same region wasasked to participate. Companies were ap-proached and visited from July to November1993.

ANALYSES

The statistical analyses were performed in astepwise order:(1) Firstly, the quality of the monitoring

methods was looked into. Factor analyses wereperformed to check the validity of the question-naire structure. Homogeneity of the scales wastested with Cronbach á. The additional valueof individual items for scales was considered.

(2) To present prevalences, descriptive analy-ses were used. Information from the employeewas always aggregated at the company level—that is, for simple yes or no questions thepercentage yes per organisation was determined,for scales average scores per organisation werecalculated. Employee responses of anorganisation were only included when at least 15employees had returned valid questionnaires(out of 25–35 distributed questionnaires).(3) The contribution of variables to explain

preventive action at company level was testedwith logistic regression analyses. Logisticregression was used because of the (sometimesextreme) skewness of the dependent variables.If variables were not a dichotomy themselves,as a rule they were dichotomised by way of amedian split. To determine the independentcontribution of the employee information, theregression analyses were performed in astepwise order. In the first step only theindependent variables as measured in theemployer interview were entered. In the secondstep the (dichotomised) employee scales wereentered as well. The significance of theincrement in ÷2 after entering the employeeinformation was tested, taking into account theincrease in degrees of freedom.

ResultsRESPONSE

It was planned to include 880 companies in thestudy. Eventually 782 did participate. In only376 companies (48%) a works council(representation of employees) was found to bepresent, and in only 292 companies (78% ofthese 376) interviews with an employees’representative could take place. In 528 compa-nies (67.5%) questionnaires were distributedamong a random sample of employees. A totalof 7717 employees completed and returned thequestionnaires. It was estimated that about74 000 employees worked in the 782 compa-nies in the study sample. The employee samplethus constituted about 10% of the totalnumber of employees. However, in only287 companies more than 15 employeesresponded.The distribution of companies in the sample

across a branch of industry, company size, and

Table 2 Distribution of response percentages of organisations across branches: as planned, resulting from the employers’interviews, employees’ questionaries, and interviews with employee representatives of the Works Council

Branch Plan n (%)

Organisations withemployer interviewsn (%)

Organisations withemployee questionnairesn (%)

Organisations with employeerepresentatives interviewsn (%)

Industry 405 (46) 388 (50) 260 (49) 142 (48)Foods and alied products (8.1) (9.5) (8.7) (9.5)Textile industry (—) (3.5) (4.0) (2.7)Clothing industry (—) (2.1) (2.7) (0.7)Printing industry (6.8) (6.6) (8.1) (7.4)Chemical industry (5.6) (4.9) (4.2) (6.7)Metal industry (9.8) (10.3) (9.5) (10.4)Machine industry (9.4) (0.3) (0.4) (0.7)Electrotechnical industry (6.2) (6.1) (6.1) (6.1)Means of transportation industry (—) (6.0) (5.5) (3.7)

Building industry (—) (0.1) (0.2) (0.3)Wholesale trade 173 (19.7) 146 (18.7) 93 (17.6) 50 (16.9)Banking and finance 238 (27.1) 198 (25.4) 141 (26.7) 101 (34.2)Banking and insurances (6.8) (6.2) (6.6) (7.8)Service sector (profit) (20.3) (19.2) (20.1) (26.4)

Cleaning companies 60 (6.8) 48 (6.1) 34 (6.4) 2 (0.7)Total 880 (100) 782 (100) 528 (100) 296 (100)

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region was generally as planned (table 2). Onlycompanies in the machine industry were repre-sented less than originally planned, whereascompanies in the transportation industry andcompanies of medium size (50–100 employ-ees) were slightly overrepresented. The compa-nies in which interviews with employee repre-sentatives had taken place were relatively large.This was to be expected as large companies(>35 full time equivalents) are legally obligedto have a works council.The non-response in interviews with em-

ployees’ representatives and in the employeequestionnaires could have resulted in some sortof selection bias. When looking into the poten-tial selection bias in interviews with employees’representatives, the only bias is that theinterviews occurred more often in the largercompanies of the present sample.The distribution of employees across bran-

ches of industry who filled in questionnaireswas almost the same as that of companies fromwhich questionnaires were received. Despitethis, the employee (questionnaire) response perorganisation was relatively large in banking andfinance, compared with industry and wholesaletrade.When comparing the distribution of profes-

sions across the diVerent branches of industry,it shows the pattern that is expected, with theexception that supervisors are overrepresentedin the data base compared with national refer-ence data.3

FACTORIAL STRUCTURE AND HOMOGENEITY OF

THE QUESTIONNAIRE DATA

Factor analysis of all employees’ answers onquestions indicating risks resulted in 12 scaleswith an Eigenvalue more than one. Because thedichotomous nature of the questions mayintroduce instability in the factor analyses,these analyses were also performed on sub-groups (men v women; older v young employ-ees). The results were almost identical in allsubgroups. In the factor analysis on the wholesample, a total of 56.5% of the variance wasexplained. The original scales were found to bequite well represented by the factor structure.

Physical load constituted the first main factor(19.7% of the variance explained). Almost allquestions on physical risks depended on thatfactor. The question on sitting had a negativeeVect on this physical load factor, whereasbending forward, or twisting the neck, andoften being in the same posture, showed norelation to it. Several of the physical load risksdid, however, also consititute an individual fac-tor (short cycle tasks, often taken postures orpostures of long duration, and vibrations).Other factors that were identified were socialrelations at work (5.8% variance explained;including the social support questions), skilldiscretion (4.7% variance explained), psycho-logical demands (3.9% variance explained),autonomy or decision authority at work (2.5%variance explained), autonomy with respect tothe workplace (2.2% variance explained), flex-ible working hours (2.1% variance explained),atmosphere at work (1.9% variance explained),and shortage of personnel (1.8% varianceexplained).Homogeneity of the original scales, indicated

by the Cronbach á, was good (0.61<á<0.85),with the exception of the scale on autonomywith respect to working conditions (á=0.10).When the questions on social support wereincluded in the scale measuring social rela-tions, the indicator of homogeneity neitherincreased nor decreased. In further analysesthe most economic short version of the socialrelations scale was used without the social sup-port questions.

CORRESPONDENCE BETWEEN RATINGS OF

EMPLOYER AND EMPLOYEE OR EMPLOYEES’REPRESENTATIVE

As the employer’s responses are dichotomousvariables, calculating correlations between em-ployer’s and aggregated employee scores oncomparable risks and health outcomes is notcompletely appropriate. An alternative—suchas the ê indicator of correspondence—doesnot, however, properly takes into account thecontinuous nature of the employee infor-mation. Correlations are considered to give asimple and concise picture of the association

Table 3 Percentage of employers who identify a specific risk factor as a problem, or health complaints to be work related

Industry Wholesale trade Banking and finance

Employer(n=388)

Employer − employeerepresentative (n=142)

Employer(n=146)

Employer − employeerepresentative (n=50)

Employer(n=198)

Employer − employeerepresentative (n=101)

Stress risks as a problem:Work pace 16.5 −14.9 13.7 −8.0 23.2 −3.0Autonomy 3.6 −4.2 0.7 −4.0 3.0 −5.0Skill discretion 9.3 −2.8 6.2 −4.0 7.6 1.0Autonomy in working cond. 4.6 −11.3 0.7 −8.0 4.5 0Relations 13.1 −5.0 6.2 −4.0 8.6 −8.9

Physical load as a problem:Force 22.2 −7.7 19.2 −4.0 8.1 1.0Dynamic load 12.9 −6.3 7.5 0 4.0 −2.0Posture 13.4 0.7 8.2 2.0 7.6 −4.0Vibrations 3.1 0 2.7 0 0 −2.0

Health outcomes as work related:Emotional exertion 27.5 −4.1 30.8 −9.4 38.9 −8.3Musculoskeletal problems 44.8 11.7 41.1 −7.6 31.3 −8.3

For those organisations from which both employer and employee representatives were interviewed, the diVerence between the percentages of employers and employeerepresentatives identifying a specific risk factor as a problem or health complaint to be work related is presented. A negative diVerence indicates that less employersthan employee representatives consider the risk to be a problem, or health outcome to be work related. Although the number of organisations in which both employ-ers and employee representatives were interviewed was less than half of the original sample, the percentage of employers that considered a specific risk to be a prob-lem generally was not very diVerent. For industry, only the “social relations at work” and “force” were more often reported to be a risk by the employers in the smallsample (diVerence >5%). In the wholesale trade, “work pace” was more often a problem in the small sample (diVerence >5%).

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between the employer’s perception, and theaverage perception of the employees in theorganisation. Also Student t tests were per-formed to test if the average employees’ scoreson risks in companies were higher whenemployers indicated these risks to be present,or to be a problem, compared with the situationwhen this was not the case. These tests werealso used to test if employees’ scores on healthoutcomes are higher in companies whereemployers say these complaints have beenraised or were considered to be work related.The t tests resulted in the same conclusion asthe correlational analyses: the correspondencein ratings on risks and health consequences waspoor between employer and employees. Therewas no correlation between the answers of theemployer to the question of whether or notemployees in their organisation were con-fronted with a specific risk, or if theyconsidered that risk to be a problem, and themean score of the scale measuring that risk

factor from employees of the same company.All but two of the correlations were equal orlower than r=0.25. The only exceptionsconcerned the risks of force (exertion) anddynamic load (0.30<r<0.41). Also no system-atic correlations were found between theanswers of employers and the mean score ofemployees from the same organisation indicat-ing that health problems had been raised in thepast year, or were considered to be workrelated.The correlations between the answers of the

employer and employees’ representative werelow to moderately high for the risks present(ranging from 0.40–0.65, depending on therisk), but were absent to moderate for the iden-tification of risks as problems (ranging from0.07 for autonomy to 0.53 for force). Employ-ers and employees’ representatives thus onlypartly agree on the identification of risks forwork stress and physical load, and disagree on

Table 4 The preventative measures reported most often on work stress and physical load according to employers(companies could have implemented more than one type of measure)

Work stress Physical load

Priority MeasuresEmployers(%) Priority Measures

Employers(%)

1 Providing training courses 6 1 Individual changes in work or tasks 442 Individual changes in work or tasks 12 2 Other tools, equipment, devices 333 Other job in company 11 3 Adjusting work station 284 Job rotation 10 4 Other job in company 215 Implementing regular work

consultation10 5 Providing training courses and

information19

6 Training course for supervisors 10 6 Individual advice 137 Job enlargement 8 7 Job rotation 138 Training course on the job 8 8 Other tasks 119 Adjusting work schedule 7 9 Physical fitness course 410 Individual counselling 7 10 Individual physical training 2

Table 5 Odds ratios (OR) (95% CI) resulting from logistic regressions on professional expertise employed by the company in the field of health andsafety, measures taken last year in general, or specifically related to work stress, to physical load and rehabilitation: only the significant predictors are shown(results from analyses on organisations with a response of > 15; n =287)

Preventive policy or measures

Professional expertise General measures Work stress Physical load Rehabilitation

OR (95% CI)(÷2=55.4, df=28,R2

ML=0.18)

OR (95% CI)(÷2=150.5, df=28,R2

ML=0.41)

OR (95% CI)(÷2=124.2, df=28,R2

ML=0.41)

OR (95% CI)(÷2=95.3, df=28,R2

ML=0.28)

OR (95% CI)(÷2=37.3, df=28,R2

ML=012)

Employee:Work pace 0.4 (0.21 to 0.84) — 2.1 (1.05 to 4.12) 0.5 (0.22 to 1.13) —Autonomy — 0.4 (0.20 to 0.97) — — —Skill discretion — — 0.4 (0.22 to 0.85) — —Physical load — — 2.6 (1.22 to 5.49) — —

Employer:Employer identifies work stress risks as aproblem — — 1.9* (0.92 to 3.97) — 1.7* (0.91 to 3.27)

Employer identifies risks for physical loadas a problem — 2.06* (0.90 to 4.74) — — —

Employer identifies exhaustion to be workrelated 2.7 (1.19 to 5.94) — 3.0 (1.39 to 6.42)

4.2 (1.74 to10.06) —

Employer identifies musculoskeletalproblems to be work related 1.8* 0.90 to 3.54 — — —

Absenteeism — — — 2.6 (1.20 to 5.79) —Involvement of employees inimplementing preventive policy 1.9* (0.98 to 3.64) 2.55 (1.18 to 5.53) — — —Good socioeconomic position of thecompany — — 3.4 (1.19 to 9.94) — —

Company size >100 employees 2.0 (1.00 to 4.08) 6.5 (2.97 to 14.12) 2.0 (1.02 to 4.02) 2.2* (0.90 to 5.16) —Use of support at branch level 2.3 (1.17 to 4.46) — 2.5 (1.25 to 5.08) 2.7 (1.27 to 5.90) —Branch activities directed at stress — — 9.0 (3.02 to 26.82) — —Branch activities directed at physical load — — 0.5 (0.23 to 1.04) — —A lot of teamwork — 3.8 (1.5 to 9.68) — 3.11 (1.09 to 8.89) —Follower of the market — — — — —A weak input of materials 2.6* (0.97 to 6.91) — — — —A weak labour market — — — — 0.5 (0.29 to 0.99)Measures were found eVective — 3.8 (1.87 to 7.58) 5.6 (2.91 to 10.95) 3.8 (1.63 to 8.69) 2.8 (1.56 to 4.94)

*0.05 < p < 0.10.

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whether these risks constitute a problem to theorganisation.Many of the employers, however, do recog-

nise the presence of work risks. Only asubgroup of them also identified these risks asa problem in their organisation.Table 3 shows the diVerence between

employers and employees’ representatives, whoboth were asked the same question. The figuresconsistently show that, in particular for therisks of work stress, a higher proportion ofemployees’ representatives considered risks tobe a problem in the company. The diVerencebetween employers and employees’ representa-tives was highest for work pace.For employers in industry and wholesale

trade the main problems were force and workpace, whereas in banking and finance workpace was by far the main problem. From table3 it can be seen that autonomy and vibrationswere rarely considered to be problems.Not only were the stress risks less often con-

sidered to be a problem by employers com-pared with employees’ representatives, but alsohealth complaints were less often considered tobe work related by employers. The only excep-tion was musculoskeletal complaints in indus-try, which were considered to be work relatedmore often by the employer than by theemployees’ representative.

PREVENTIVE ACTION, ESPECIALLY DIRECTED AT

WORK STRESS AND PHYSICAL LOAD

Responses of employers and employees’ repre-sentatives on the questions about preventivemeasures taken in the past 12 months coin-cided to a large extent. The figures show thatthere has been an important increase in theamount of preventive actions since 1993. Itseems probable that this recent increase is dueto the updated legislation already described.About 21% of the companies publish a

working conditions policy plan, whereas about20% of the companies are developing such aplan. In about 30% of these plans physical loadis an important topic, whereas in only 16% iswork stress important. A general risk assess-ment on working conditions has been per-formed by 25% of the employers. One out offive companies has published a report on itsworking conditions policy for the previousyear, including an overview of sickness absen-teeism, turnover, and work disablement. Abouthalf of the companies state that they relate theirworking conditions policy to other manage-ment topics, in order of importance: policytowards sickness absenteeism; social policy;environmental policy; and total quality man-agement.In the previous year about 12% of the

employers have carried out a study into physi-cal load, and only 3% into stress. Table 4 showsthe most reported preventive measures to limitwork stress and physical load. As there weregenerally only minor diVerences between theratings given by the employers and by theemployees’ representatives, only the employer’sinformation is presented here.Table 4 shows that preventive measures

against physical work load were much more

popular than measures against stress. Preventivemeasures directed at either stress or physicalload were related to changing the work situationand the individual employee (improving workcapacity). However, when comparing preventivemeasures against stress with those against physi-cal load, the most prominent preventive meas-ures against physical load were more oftendirected at changing the work situation.

OBJECTIVES FOR IMPLEMENTING PREVENTIVE

MEASURES TO LIMIT WORK STRESS AND PHYSICAL

LOAD

Those companies that reported taking preven-tive actions against work stress or physical loadwere asked their reasons for doing so (maxi-mum of three per company). According to boththe employers and the employees’ representa-tives there were three main reasons: decreasingsickness absenteeism (29%, both employersand employees’ representatives), increasingproductivity (employers 13%, employees’ rep-resentatives 8%), and increasing employeemotivation (employer 11%, employees’ repre-sentatives 8%).About 50% of all employers said that they

have evaluated their preventive actions (25%according to the employees’ representatives).In general, the employers reported variouspositive eVects: 68% of those employers whoevaluated their preventive actions reportedpositive eVects on employee motivation (36%by the employees’ representatives), 60% re-ported a decrease in sickness absence (26% bythe employees’ representative), almost 50%reported a better social climate (21% by theemployees’ representative), and 40% reportedan improved productivity (24% by the employ-ees’ representative). The data clearly show thatpreventive actions were evaluated more posi-tively by employers than by employee repre-sentatives.

FACTORS FACILITATING PREVENTIVE ACTION

Table 5 shows the results of the logistic regres-sions for various dependent measures: theamount of professional expertise present in theorganisation; the number of general preventivemeasures taken; number of measures takendirected at the prevention of work stress; thenumber of measures taken directed at the pre-vention of physical load; as well as measuresdirected at rehabilitation (tertiary prevention).In all analyses, the dependent measure wassplit at the median, which meant that the refer-ence in all analyses was zero measures.Table 5 shows that the predictor sets gener-

ally explained the dependent measures well, inparticular the general and specific measures,and to a lesser extent the professional expertise,and the rehabilitation policy. The strength ofthe logistic model is represented by R2

ML, whichwas calculated with the Maddala formulabased on a transformation of the likelihood-ratio

R2ML = 1−e−(÷

2 /N).26

The R2ML is considered comparable with the

R2 in linear regression.

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Information of the employees only contrib-uted significantly to the explanation of com-pany diVerences in the number of stress meas-ures taken. The employee information tendedto contribute to the number of generalmeasures taken, but not at all to the number ofmeasures directed at physical load and rehabili-tation.Independent factors associated with compa-

nies that have increased their professionalexpertise in the past 12 months compared withthose that have not were: employer infor-mation, employer identified emotional exhaus-tion and musculoskeletal problems as workrelated; were larger in size; used support inprevention at branch level; tended to involveemployees in implementing the preventivepolicy; and to have a weak input of materials(probably relevant in wholesale trade andindustry). Surprisingly, the companies thathave taken on professional expertise scoredpoorly on work pace, according to the employ-ees.Independent factors diVerentiating compa-

nies that have taken general measures in thepast 12 months compared with those that havenot taken any (employer information) wereinvolving employees in implementing preven-tive policy; were larger; had a lot of team work;and measures were found to be eVective. Therewas a tendency for risks for physical load to beconsidered a problem. According to theemployees, the autonomy was high (lowemployee score) in these companies.Independent factors diVerentiating compa-

nies that have taken measures to prevent workstress in the past 12 months compared withthose that have not taken any (employer infor-mation) were: employer identified emotionalexhaustion to be work related; a bettersocioeconomic position; larger companies; useof support at branch level, branch activitieswere specifically directed at stress; and meas-ures were found to be eVective. There was alsoa tendency for employers to identify work stressrisks as a problem, and for that branch ofindustry to be low on measures against physicalload. Information from the employees contrib-uted considerably in diVerentiating betweencompanies that had taken measures againstwork stress in the past 12 months and thosethat had not.More measures had been taken incompanies where employees indicated a highwork pace, high skill discretion, and highphysical load.Independent factors diVerentiating compa-

nies that have taken measures to prevent physi-cal load in the past 12 months and those thathave not taken any (employer information)were: employer identified emotional exhaus-tion and absenteeism to be work related; use ofsupport at branch level; a lot of team work; andmeasures to be found eVective. There was atendency for larger companies to take more ofthese kinds of measures.Hardly any diVerentiating factors between

companies that do or do not do anything aboutrehabilitation were found. The few independ-ent factors diVerentiating companies that havetaken rehabilitative measures in the past 12

months and those that have not taken any(employer information) were a weak labourmarket and measures were found to beeVective. There was a tendency for employersto identify risks for work stress to be a problem.Thus independent factors that at least two

out of five times consistently diVerentiatedbetween companies that have taken measures,either general or more specific ones, were: theemployer to recognise either a risk factor as aproblem or health outcomes to be work related;a larger organisation; support at branch level;whether the employer considered the measuresor policy to be eVective; and more employeeinvolvement (only for the general measures).The employer’s identification of a symptombeing work related more often contributed topreventive action than the employer’s identifi-cation of risks at work as problems.The regression analyses have only been per-

formed on the 287 companies for which bothemployer and employee information (>14employee) was available, as a large enoughemployee response was obtained from less thanhalf of the companies that originally partici-pated in the study. The analyses of the first stepin the logistic regression with employer infor-mation only was repeated for the whole sampleof 778 companies. In general, almost allvariables, which contribute to the five depend-ent measures of preventive action in the firststep in the logistic regression on the small sam-ple (n=287), emerged as significant predictorsin the first step on the total sample (n = 778) aswell, with comparable odds ratios. Only smalldiVerences were found between the results ofthe two analyses, largely explained by the lowerthreshold for significant odds ratios in the largesample.

Discussion and conclusionsIn this study information is provided on theprevalence of risks and consequences, as iden-tified by employees, employees’ representa-tives, and employers, as well as information onthe prevalence and determinants of preventiveactions at the company level, in three majorbranches of industry. The results lead to theconclusion that employers do recognise thatrisk factors at work can be a problem. In com-parison with employees or employees’ repre-sentatives, however, they often seem to under-estimate the problem. This is particularly thecase for work stress risks. It might be arguedthat it is the employee or employees’ repres-entative who is overestimating, although it isdiYcult to tell the norm in situations in which,by way of self report, information is gatheredfrom diVerent people with diVerent interests.Self reporting, however, gives valuable infor-mation and publications consistently indicatethat the self reported presence of stress risksand health problems themselves do havesignificant and independent prognostic value inpredicting mortality and morbidity.27–30 Selfreporting, also from employees, must thereforealways be considered as a potentially importantsignal.From the risks mentioned for work stress,

work pace was most often considered to be a

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problem. Relations at work were regularly con-sidered problematic as well. Autonomy, on theother hand, was hardly considered to be aproblem, both by employers and by employees’representatives. These results accord, to someextent, with the results from the study by theEuropean Foundation, which identified theDutch employees relative to employees in otherEuropean Union countries as having the mostunfavourable work pace, but the most favour-able autonomy.5 6 Within the framework of thejob demand job control model—one of themost popular work stress models at present—itis stated that the combination of high jobdemands and low control are especially relatedto several ill health outcomes. From thesetheoretical notions, job strain is expected not tobe very high in the Dutch work force. Thescores on psychological health complaints asmeasured in the European Union surveyconfirm this finding. These figures, however,conflict with the notion that so many employ-ees drop out of work due to psychologicalproblems (and one third of all drop out due tohealth problems). As the European Union sur-veys were cross sectional in nature, the hypoth-esis of a healthy worker selection may explainthis contradiction.Longitudinal studies of the processes of

dropout in greater detail are, however, stillscarce and therefore highly warranted.Another explanation for the high work pace

in combination with high autonomy, lowpsychological health complaints, but a highdropout from work due to psychological prob-lems may be the changes in the work situation:the increase in flexibility (flexible workinghours, flexible work places) and working withinformation. These changes make it possiblemore often to do work at home, and in the eve-nings and weekends.31 This means that al-though the employee may be very autonomousand is able to develop skills, work and privatelife become more and more entangled. It isreported that chronic entanglement of workand private life is associated with more chronicfatigue.31

The finding that employers seem to underes-timate risks in general, and stress risks inparticular, may be interpreted by employersstill failing to identify stress as a problem. Thismay also explain why relatively few measuresdirected at the reduction of work stress werereported.The finding that employee information

significantly contributed only to the measuresto limit stress may indicate that especially in thecase of work stress, measures are taken just tomeet the complaints about stress risks by theemployees. Stress directed measures were,however, likely to be taken also when the finan-cial status of the organisation was considered tobe good.The results showed a strong increase in pre-

ventive measures taken the year preceding theinterview than before. This increase is probablyrelated to the implementation of the updatedand renewed legislation on occupational healthand safety in The Netherlands, which occurreda few months after the launch of this study. The

reported preventive measures were directedboth at the work and at the workers. Preventivemeasures against physical load were found tobe much more popular than those for workstress. Consistent with other publications,training was the most common measureagainst work stress, and specific work directedmeasures were taken less often. Kahn andByosiere32 have commented on this “flood ofpractitioner activity in the field of stress reduc-tion and stress management”. Today, stressmanagement seems to be a booming marketand an industry of its own.33 This market hasbeen characterised by Martin34 as a market inwhich the most widespread demand is rapid,low cost training that at least quiets employees’complaints, if not their stress.In contrast to measures on work stress,

measures on physical load are primarilydirected towards the workplace and work tasks,and are most often of an ergonomic nature.Measures directed at physical load are oftentaken at the worker level, although adjustmentsto the workstation and to tools, and modifica-tion or use of equipment and devices are alsocommon. Measures directed towards indi-vidual capabilities of the worker are lesscommon in the domain of physical load.A variable that was often found to be associ-

ated with general measures in particular is ahigh degree of employee participation. Vari-ables related to general as well as specificmeasures are: a larger size of the organisation;more use of support in prevention at branchlevel; and the fact that the measures were con-sidered to be eVective by the employer.Reviews on intervention studies implementingdiVerent kinds of preventive measures35 36 showthat employee participation can be an impor-tant success factor for specific measures aswell.More use of support at branch level is

systematically found to be related to more pre-ventive action. This may, however, be related tothe oVer at branch level, as well as to a moreactive role of the company itself. The fact thatspecific branch activities were found to inde-pendently contribute to specific preventivemeasures leads to the conclusion that both thespecific branch activities directed either at workstress or physical load and a more active role ofthe company itself, facilitate specific preventiveactions at the company level.The logistic regressions that diVerentiate (and

may be able to oVer prognosis) between compa-nies that took preventive measures and thosethat did not, do not completely coincide with thereasons the employers provide for investing inpreventive action. The main objective, and maineVect as reported by the employers for takingpreventive measures, is a reduction in absentee-ism, next to increasing productivity (not fullydiscussed in this study) and increasing motiva-tion. Absenteeism was only found to signifi-cantly enter the logistic regression on measuresdirected at physical load. Relations at work,which aVect motivation, either as the employee(average) score, or as the employer’s recognitionof this risk factor as a problem, was not found tosignificantly contribute to the explanation of any

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preventive measure. It is striking that preventivemeasures on physical load are not associatedwith the employers’ identification of physicalload as problematic or with their perception thatmusculoskeletal problems are work related, but,apart from absenteeism, are associated stronglywith employers’ identification of work relatedemotional exhaustion. This could mean thatemployers are focusing measures mainly on highenergetic (mental or physical) loads and are lessfamiliar with the work related health eVects ofmore static working situations and measures toprevent these types of problems. The relativelylow percentage of employers (and employees’representatives) in banking and finance report-ing posture as a problem and reportingmusculoskeletal problems as work related (table3) could be indicative of this phenomenon.The explanation of measures directed at

rehabilitation is an exception on the more gen-eral statement already made. Rehabilitativemeasures were only marginally explained.Some explanatory power comes from a weaklabour market, and when measures wereconsidered to be eVective.The logistic regressions showed considerable

stability among the predictor sets: both for thevarious dependent measures, and across sam-ple size. For sample size, it was companies fromthe branches of industry and wholesale trade inparticular that were lost when only companieswith a response of 15 employees or more wereused. This reduction resulted, however, only inminor changes in the predictor set that bestexplained the dependent variable, both for thespecific variables that emerged, and the magni-tude of the odds ratios. This stability in predic-tor sets despite a relative selective reduction insample size suggests that the predictor sets ofthe preventive measures are relatively similaracross diVerent employment sectors.This study of monitoring is quite unique in

its aims, its specific focus on work stress andphysical load, and on the explanation ofpreventive measures with information fromboth employers and employees. Of course wehave to be careful to infer causal relations fromthe cross sectional data in the present study.Also, preventive action was taken as thedependent variable, and was assumed to beexplained by the perception on risks, healthoutcomes, and some general organisational andbranch aspects, instead of the other wayaround: risks and consequences as to be deter-mined by preventive action. Both directions ofcausality are plausible, and should both betested in the future, when a longitudinal dataset is present. Especially when testing the inde-pendent eVects of employee information,measures should be taken to increase the sam-ple size of employees.

This research was supported by the Dutch Ministry of SocialAVairs and Employment. This paper could not have been writ-ten without the eVorts of data collection by the (former) wagecontrol service of this Ministry.

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