Physical and psychosocial risk factors formusculoskeletal disorders in New Zealand nurses,postal workers and office workers

Helen Harcombe,1 David McBride,1 Sarah Derrett,2 Andrew Gray1

ABSTRACTObjective To investigate the association of physical andpsychosocial risk factors with musculoskeletal disorders(MSDs) in New Zealand nurses, postal workers andoffice workers.Design A cross-sectional postal survey asking aboutdemographic, physical and psychosocial factors andMSDs.Participants A total of 911 participants was randomlyselected; nurses from the Nursing Council ofNew Zealand database (n¼280), postal workers fromtheir employer’s database (n¼280) and office workersfrom the 2005 electoral roll (n¼351).Outcome Measures Self-reported pain in the low back,neck, shoulder, elbow, wrist/hand or knee lasting morethan 1 day in the month before the survey.Results The response rate was 58%, 443 from 770potential participants. 70% (n¼310) reported at leastone MSDs. Physical work tasks were associated withlow back (odds ratio (OR) 1.35, 95% CI 1.14 to 1.6),shoulder (OR 1.41, 95% CI 1.17 to 1.69), elbow (OR1.14, 95% CI 1.13 to 1.83) and wrist/hand pain (OR 1.39,95% CI 1.15 to 1.69). Job strain had the strongestassociation with neck pain (OR 3.46, 95% CI 1.30 to 9.21)and wrist/hand pain. Somatisation was weakly associatedwith MSDs at most sites. Better general and mental healthstatus were weakly associated with lower odds of MSDs.Conclusions In injury prevention and rehabilitation thephysical nature of the work needs to be addressed formost MSDs, with modest decreases in risk seeminglypossible. Addressing job strain could provide significantbenefit for those with neck and wrist/hand pain, whilethe effects of somatisation and the promotion of goodmental health may provide smaller but global benefits.

Musculoskeletal disorders (MSDs) are a leadingproblem in nearly all industries, from thoseinvolving heavy manual work to those with moresedentary activities. In the general population theseconditions are also common1; they ‘are the mostfrequent causes of physical disability, at least indeveloped countries.’2 Risk factors are multifacto-rial and include physical and socio-organisationalfactors at work and also cultural and personalfactors, and this complex model needs to beunderstood in order to modify the risks.3 Physicalfactors are probably best understood.4 Socio-organisational factors (job control, demand andsupport) and personal factors (general and mentalhealth) have been studied but are less well under-stood. An emerging factor, a tendency to worryabout disease (somatisation) is now under investi-gation in an international longitudinal study,

Cultural and Psychosocial Influences on Disability(CUPID). The relative importance of these factorsand how they differ in their effects across commonoccupations, and internationally, is not yet wellunderstood.A previous report showed a high prevalence of

MSDs in nurses, postal workers and office workersat baseline in this New Zealand component of theCUPID study.5 Few studies have investigated riskfactors for MSDs in these New Zealand workers. Aprospective study included nurses in an investiga-tion of risk factors for acute low back painbecoming chronic,6 and a cross-sectional study hasinvestigated risk factors for MSDs in clericalworkers and cleaners.7 Other studies reported thatMSDs prevalence differed among workers in thesame occupational groups, for example low backpain was more common among nurses who workedon particular wards,8 and the prevalence of upperlimb pain was higher among keyboard workerscompared with non-keyboard workers in a study ofclerical workers.9 To our knowledge no otherstudies have investigated risk factors for MSDs inthese ‘at risk’ New Zealand workers. This paperdescribes the association between physical andpsychosocial risk factors and MSDs in NewZealand nurses, postal workers and office workers.

METHODSDesignA cross-sectional postal survey of nurses, postalworkers and office workers using computers. Thestudy received ethical approval from the NewZealand Multi-Region Ethics Committee.

Study participantsThe CUPID study required participants to be agedbetween 20 and 59 years, working in one of thethree target occupations and in their current job forat least a year. They also had to be resident in NewZealand at the time of the survey in 2007. Powercalculations were conservatively based on thelowest 1-month prevalence estimate (40%) ofMSDs lasting for at least 7 days in the generalpopulation of New Zealand reported by Taylor.10 Aminimum of 350 completed responses allowed usto investigate up to 14 predictors simultaneously(as this would give 140 cases) using the recom-mendations of Peduzzi et al.11 Taking factors suchas an anticipated response rate of 50%, stability ofemployment and accuracy of self-reported occupa-tion on the electoral roll into account, a total of 911workers was randomly selected and invited toparticipate in the study. Nurses were selected from

1Department of Preventive andSocial Medicine, University ofOtago, Dunedin, New Zealand2Injury Prevention ResearchUnit, Department of Preventiveand Social Medicine, Universityof Otago, Dunedin, New Zealand

Correspondence toDr David McBride, Departmentof Preventive and SocialMedicine, University of Otago,PO Box 913, Dunedin 9054,Otago, New Zealand;david.mcbride@otago.ac.nz

Accepted 10 September 2009

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the Nursing Council of New Zealand database (n¼280), postalworkers from an employer ’s database (n¼280) and officeworkers from the New Zealand 2005 electoral roll (n¼351).

Definition of injuryMSDs were defined as self-reported pain at the low back,neck, shoulder, elbow, wrist/hand or knee lasting for more thana day in the month before the survey. Questions were similar tothe Standardised Nordic Questionnaires for MSDs andwere accompanied by a diagram showing the area of the body inquestion.12

SurveyThe UK CUPID team designed a core questionnaire developedfrom previous research (eg, Palmer et al13 and Smedley et al14)including demographic, physical and psychosocial factors.Additional items, specific to the New Zealand survey were alsoincluded such as a measure of general health status. Eightphysical work tasks (box 1) were aggregated to give a ‘total taskscore’. Psychosocial work factors were assessed by the WhitehallII psychosocial work questionnaire.15 This consists of 25 ques-tions in three principal domains, recoded so that high scoresequal high job control, high job demands and high support.Scores were added for each subscale and divided into highmedium and low tertiles. High job strain was defined as lowcontrolehigh demands, low job strain was high controlelowdemands and medium job strain was the remainder (lowelow,highehigh or medium in either subscale.)

Seven questions from the Brief Symptom Inventory16 wereused to investigate somatisation. Each item was scored on a five-point scale (0e4) with total possible scores of 0e28. Becausetwo Brief Symptom Inventory questions could relate directly toMSDs (numbness or tingling and feeling weak) somatisationscores were also calculated omitting these items. Mental healthstatus was assessed by the Mental Health Inventory-5,17 fiveitems each with a six-point scale; self-efficacy using the GeneralSelf-Efficacy Scale,18 10 items scored from one to four (possiblescores 10e40) and general health status using the EQ-5D.19

The length of time participants had been in their current jobwas classified as 1e5 years or greater than 5 years. Participantswere asked how secure they felt their job would be if theyhad a significant illness that kept them off work for 3 months(job security) with four possible response options that weredichotomised for analysis (ie, low/high job security). Job satis-faction was assessed by asking how satisfied participants hadbeen with their job as a whole, taking everything into consider-ation. The four possible responses were once again dichotomisedfor analysis (ie, low/high job satisfaction).

StatisticsMSDs were investigated by anatomical site considering alloccupational groups together. The association between riskfactors and each site of MSDs was analysed by multiple logisticregression adjusting for occupation, age, sex and body massindex (BMI). Fewer participants reported elbow pain, so for thistype of MSDs only occupation and age were entered into themodel. Physical work tasks were also adjusted for when analy-sing psychosocial factors. Data were analysed using Stata 9statistical software.20

RESULTSOf the 911 people invited, there were 770 eligible participants; ofthese 443 (58%) agreed to participate. Of the 443 participants,low back pain was reported by 31% (n¼136), neck pain by 29%(n¼128), shoulder pain by 27% (n¼120), elbow pain by 12%(n¼52), wrist/hand pain by 23% (n¼104) and knee pain by 22%(n¼98).Table 1 shows the work organisational factors investigated.

Physical work tasks showed weak but significant associationswith MSDs of the low back, shoulder, elbow and wrist. Theremaining factors showed no significant effects.

Box 1 Physical work tasks on an average working day

< Keyboard or typewriter use for more than 4 h in total< Repeated wrist or finger movements for more than 4 h in total< Repeated bending and straightening of the elbow for longer

than 1 h in total< Reaching, pushing or pulling< Hands above shoulder height for more than 1 h in total< Lifting weights 25 kg or more by hand< Climbing up or down more than 30 flights of stairs< Kneeling or squatting for longer than 1 h in total

Table 1 Work organisational factors

Sample size (n[443) Low back pain (n[136) Neck (n[128) Shoulder (n[120) Elbow (n[52) Wrist/hand (n[104) Knee (n[98)

Variable (reference)p Value p Value p Value p Value p Value p ValueOR (95% CI) OR (95% CI) OR (95% CI) OR (95% CI) OR (95% CI) OR (95% CI)

Time in job (1e5 years)>5 years

0.3011.32 (0.78, 2.23)

0.3080.77 (0.46, 1.28)

0.5541.18 (0.68, 2.04)

0.9831.01 (0.50, 2.02)

0.0930.61 (0.34, 1.09)

0.5151.22 (0.69, 2.24)

Contract type (permanent)Other

0.4030.77 (0.41, 1.43)

0.3191.36 (0.74, 2.49)

0.8401.07 (0.56, 2.04)

0.6520.80 (0.65, 2.07)

0.6750.85 (0.41, 1.78)

0.9831.01 (0.50, 2.04)

Work schedule (regular day)Other

0.5981.15 (0.68, 1.97)

0.7210.91 (0.52, 1.56)

0.6151.16 (0.65, 2.07)

0.1681.73 (0.79, 3.79)

0.9650.99 (0.53, 1.82)

0.5840.85 (0.47, 1.52)

Type of shift (regular day)Regular night shiftOther

0.7680.71 (0.28, 1.79)0.87 (0.38, 1.97)

0.0922.81 (1.05, 7.48)1.15 (0.45, 2.96)

0.5250.66 (0.26, 1.66)0.63 (0.26, 1.55)

0.8760.94 (0.28, 3.22)1.33 (0.37, 4.75)

0.2021.89 (0.64, 5.55)2.69 (0.88, 8.23)

0.6221.56 (0.52, 4.62)1.55 (0.57, 4.23)

Hours/week main job 0.7231.00 (0.98, 1.03)

0.2301.01 (0.99, 1.04)

0.9731.00 (0.98, 1.02)

0.4211.01 (0.98, 1.05)

0.6811.01 (0.98, 1.03)

0.2641.01 (0.99, 1.04)

Hours/week total jobs 0.4021.01 (0.99, 1.03)

0.1101.02 (1.00, 1.04)

0.3351.01 (0.99, 1.03)

0.5471.01 (0.98, 1.04)

0.7341.00 (0.98, 1.03)

0.2271.01 (0.99, 1.04)

Physical work tasks 0.0011.35 (1.14, 1.60)

0.2941.09 (0.92, 1.30)

<0.0011.41 (1.17, 1.69)

0.0031.14 (1.13, 1.83)

0.0011.39 (1.15, 1.69)

0.1641.14 (0.95, 1.38)

OR, odds ratio.

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Table 2 presents psychosocial work factors. Job strain showedthe strongest association with MSDs, with statistically signifi-cant associations for neck and wrist/hand pain and an increasedodds ratio (OR) for low back pain.

Job dissatisfaction was significantly associated with shoulderMSDs, with a non-significantly elevated risk for low back pain.

Somatisation showed consistent and significant but weakassociations with MSDs (table 3). After excluding the variablespotentially associated with MSDs, (numbness or tingling, andfeeling weak), somatisation was no longer associated withshoulder pain (p¼0.061) but remained associated with low back,neck and knee pain.

Better general and mental health was associated with lowerodds of shoulder pain and mental health with neck pain (table 3).

DISCUSSIONPrincipal findingsPhysical work tasks and somatisation were the factors mostconsistently associated with MSDs. Physical work tasks showedmodest increases in OR, strongest (in the order of a 40%increase) for low back, shoulder and wrist/hand disorders.Somatisation was significantly associated with complaints atthe low back, neck, shoulder and knee, with weak increases inOR of between 7% and 11%. Job strain showed the strongestoverall associations (OR of up to 4.1), followed by job dissatis-faction, which was associated with low back and shoulder pain.Better mental health was weakly associated with neck andshoulder pain (decrease in OR of 3e11%), better general healthshowing little effect. Job insecurity, work schedule, contracttype, hours worked and self-efficacy showed no association withMSDs.

Strengths of the studyWe addressed a wide range of potentially important physicaland psychosocial risk factors, and physical factors wereadjusted for in the analysis of psychosocial factors. This isimportant as previous literature has been criticised for notcontrolling for physical factors when analysing psychosocialfactors.21

We used validated questionnaires in the survey, for examplethe Whitehall II measure of psychosocial work factors and theEQ-5D questionnaire to measure general health status.15 19

Weaknesses of the studyThe response rate of 58% is comparable with a previous study ofMSDs in the New Zealand general population,10 and resulted inadequate power to detect possible risk factors. It may, however,have introduced respondent bias and unfortunately we knowlittle about the non-responders. However, this paper focuses onexploring associations that are unlikely to be unduly influencedby this. The random sampling reduces the possibility of selec-tion bias.The cross-sectional design means that the sequence of

causation cannot be demonstrated; however, the prospectivecomponent will address this.Sources of bias could be present due to the self-reported nature

of the data, for example participants with MSDs may morefrequently report exposure to physical and psychosocial riskfactors, tending to increase the associations. Recall bias wasreduced as far as practicable by analysing only the data collectedfrom MSDs reported in the month before the survey.Although age, sex, occupation, BMI and physical work tasks

were controlled for when possible (few episodes meant that sex

Table 2 Psychosocial work factor associations with MSDs reported at specific anatomical site

Sample size (n[443) Low back pain (n[136) Neck (n[128) Shoulder (n[120) Elbow (n[52) Wrist/hand (n[104) Knee (n[98)

Variable (reference)p Value p Value p Value p Value p Value p ValueOR (95% CI) OR (95% CI) OR (95% CI) OR (95% CI) OR (95% CI) OR (95% CI)

Job satisfaction (satisfied)Dissatisfied

0.0641.86 (0.96, 3.60)

0.4180.73 (0.34, 1.56)

0.0222.23 (1.12, 4.43)

0.9381.04 (0.38, 2.89)

0.4690.73 (0.31, 1.71)

0.7470.88 (0.39, 1.96)

Job security (safe)Unsafe

0.5460.84 (0.48, 1.48)

0.8081.07 (0.61, 1.87)

0.2081.43 (0.82, 2.51)

0.2710.62 (0.26, 1.46)

0.6641.15 (0.62, 2.12)

0.5200.81 (0.42, 1.54)

Job strain (low)MediumHigh

0.0682.45 (1.12, 5.37)2.85 (1.01, 8.03)

0.0291.43 (0.69, 2.98)3.46 (1.30, 9.21)

0.3421.58 (0.72, 3.49)2.18 (0.76, 6.24)

0.1691.95 (0.65, 5.92)0.61 (0.10, 3.73)

0.0234.13 (1.40, 12.22)2.33 (0.57, 9.51)

0.2882.01 (0.84, 4.86)2.07 (0.64, 6.71)

Social support (low)MediumHigh

0.0560.59 (0.34, 1.01)0.56 (0.32, 0.96)

0.8901.06 (0.62, 1.81)0.92 (0.53, 1.59)

0.2900.75 (0.43, 1.32)0.64 (0.36, 1.14)

0.6940.98 (0.48, 2.00)0.72 (0.33, 1.59)

0.4490.90 (0.50, 1.63)0.67 (0.36, 1.26)

0.3600.64 (0.34, 1.18)0.80 (0.44, 1.46)

MSDs, musculoskeletal disorders; OR, odds ratio.

Table 3 The association between personal factors and risk of MSDs

Sample size (n[443) Low back pain (n[136) Neck (n[128) Shoulder (n[120) Elbow (n[52) Wrist/hand (n[104) Knee (n[98)Variable p Value p Value p Value p Value p Value p Value

OR (95% CI)* OR (95% CI) OR (95% CI) OR (95% CI) OR (95% CI) OR (95% CI)

Somatisationy 0.0011.10 (1.04, 1.16)

0.0011.10 (1.04, 1.16)

0.0151.07 (1.01, 1.13)

0.3591.03 (0.97, 1.10)

0.0621.06 (1.00, 1.12)

0.0011.11 (1.04, 1.18)

Self-efficacy 0.9911.00 (0.95, 1.05)

0.1670.96 (0.91, 1.02)

0.6551.01 (0.96, 1.07)

0.4101.03 (0.96, 1.11)

0.6380.99 (0.93, 1.05)

0.6481.01 (0.95, 1.08)

Mental health 0.2770.97 (0.91, 1.03)

<0.0010.89 (0.84, 0.94)

0.0180.93 (0.87, 0.99)

0.2661.06 (0.97, 1.16)

0.0710.94 (0.88, 1.01)

0.1940.96 (0.90, 1.02)

General healthz 0.0760.99 (0.97, 1.00)

0.0580.98 (0.97, 1.00)

0.0240.98 (0.97, 1.00)

0.8391.00 (0.98, 1.02)

0.6231.00 (0.99, 1.02)

0.3490.99 (0.98, 1.01)

*Odds ratios (OR) are for per unit change in these continuous measures.yCalculated using all seven somatisation items of the Brief Symptom Inventory.16

zUsing the EQ-5D 0-100 visual analogue scale.19

MSDs, musculoskeletal disorders.

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and BMI could not be controlled for in elbow pain), we cannotrule out other confounders.

Comparison with other studiesPhysical work-related factors have been shown to have associ-ations with most MSDs, especially in the low back, neck,shoulder, elbow and wrist/hand, where there are a combinationof risk factors (force, posture and repetition).4 The only otherwork organisation factor of note was the association with neckpain when comparing regular day shift workers with night shiftworkers; however, this did not reach statistical significance. Wefound no association between length of time in job, contracttype or hours worked per week. Overall length of service wasnot significantly associated with back pain in a study of nursesworking in Hong Kong;22 however, an association was found ina study of institutional aides in Canada.23 A study of over 15 000workers in Europe reported a 21% increase in the risk of having‘muscular pain’ in non-permanent workers.24 Unfortunately, asless than 20% of participants in the current study were on non-permanent contracts we could not examine this more closely.Some studies looking at hours worked have been negative25 andsome positive.26

Waddell27 reported consistent evidence that job dissatisfactionis associated with low back pain, with OR (or relative risks) ofbetween 1.4 and 2.4. The effect size (an OR of 1.86) for thosedissatisfied with their job in our study is within this range. Poorjob security has been associated with MSDs in previousresearch28 but most of our participants had good job security,with approximately 80% in each group reporting their jobswould be ‘safe’ or ‘very safe’ if they were to have a significantillness that kept them off work for 3 months. The lack ofassociation in our study may be a true effect, but it might also bebecause of economic factors such as the low unemployment ratein New Zealand at the time of the study.

Waddell27 found evidence for an association between low backpain and job strain to be insufficient. Several prospective studieshave reported an association between ‘work stress’ and self-reported pain and discomfort25 and MSDs in the low back,shoulder, forearm and knee;29 however, the latter did not appearto account for physical work tasks, which could have meant theassociation was overestimated. A large well-designed studyinvestigating neck and shoulder pain in workers in Sweden didtake into account both mechanical factors and job strain, andfound that both acted independently, with synergistic effects(interaction) only in women.30

A review of work-related musculoskeletal health and work-related social support found that ‘there is good evidence for anassociation between poor social support and an increased risk inmusculoskeletal morbidity ’,31 but we found workplace socialsupport was only associated with low back pain. However, notall previous studies have been positive: no association was foundbetween social support and neck/shoulder pain in a large studyof workers in Denmark.32

The associations between somatisation and MSDs in thelow back, neck, shoulder and knee were positive but weak.Other cross-sectional studies have reported an associationbetween somatisation and aspects of MSDs such as self-reported disease burden and disability,33 chronic and disablingpain of the low back, knee and upper limb34 and low backpain.35 Cross-sectional studies cannot, however, determine thedirection of association. In prospective studies somatisation atbaseline was predictive of future forearm pain36 and chronicwidespread pain37 in the general population. It has also beenshown to be a predictor of the transition from acute to chronic

low back pain in a systematic review (albeit based on only twostudies).38

A cross-sectional study in the general population of NewZealand found an association between low general self-efficacyand disability in those with self-reported chronic musculoskel-etal pain39 in contrast to our study. However, we did not look atchronic pain specifically, participants in our study had to beworking and we investigated the association with musculo-skeletal pain rather than associated disability, which mayexplain the difference.Better mental health status was associated with lower odds of

neck and shoulder pain. Although the effect size in the currentstudy was small, the association is consistent with several largeprospective studies that have found that poor mental health atbaseline was predictive of neck40 and neck/shoulder pain.32 Abetter general health status was associated with lower odds ofshoulder pain, although the effect size was small. A study in theNew Zealand general population also reports poor health-relatedquality of life scores for people with MSDs.10

Recommendations for future researchThis study looked at three occupations that are common both inNew Zealand and worldwide, encompassing tasks that give riseto a spectrum of MSDs. The range of physical and psychosocialfactors are likely also to be found in other workers and indeedthe general population. Although this baseline component islimited in addressing the direction of causation, the longitudinalcomponent is expected to elucidate the temporal associationbetween cause and effect.

CONCLUSIONSPhysical work tasks remain the most consistent risk factors forMSDs, and the psychosocial factors of low job strain and jobdissatisfaction have strong effects when they occur. Althoughgood general and mental health is important, and lack ofsomatisation a good attribute, these may be less important withregard to prevention. Although MSDs are somewhat heteroge-nous as regards risk factors, in prevention and rehabilitation thephysical nature of the work needs to be addressed for most

What this study adds

< Physical work tasks were associated with MSDs of the lowback, shoulder, elbow and wrist/hand.

< The strongest associations were seen between job strain andneck and wrist/hand complaints.

< A greater number of non-physical factors were associatedwith neck pain.

< Somatisation had a small, but global, association; bettermental health status was associated with a lower odds ofneck and shoulder disorders.

What is already known on this subject

< New Zealand nurses, postal workers and office workers havea high prevalence of MSDs.

< Personal, work organisation and work-related psychosocialfactors are all associated with MSDs.

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MSDs, with modest decreases in risk seemingly possible.Addressing job strain could provide significant benefit for thosewith neck and wrist/hand pain, whereas the effects of somati-sation and the promotion of good mental health may providesmaller but global benefits.

Acknowledgements Professor David Coggon, of the UK Medical Research CouncilEpidemiology Resource Centre, is the central co-ordinator of the CUPID study. Theauthors are most grateful for the assistance and advice of Sarah Dean, RebbeccaLilley and Colin Cryer from the University of Otago for their helpful comments onearlier versions of this paper.

Funding This study was funded by the Health Research Council of New Zealand.

Competing interests None.

Ethics approval This study was conducted with the approval of the the New ZealandMulti-Region Ethics Committee.

Contributors HH helped to plan the study, collected the data, performed the analysisand wrote the draft. DMcB (guarantor) and SD were HH’s masters thesis supervisorsand helped to plan the study, advised on the analyses and wrote the re-drafts. AG,statistician, helped plan the analysis and was also involved in the interpretation ofresults.

Provenance and peer review Not commissioned; externally peer reviewed.

REFERENCES1. Punnett L, Wegman DH. Work-related musculoskeletal disorders: the epidemiologic

evidence and the debate. J Electromyogr Kinesiol 2004;14:13e23.2. World Health Organisation. The burden of musculoskeletal conditions at the start

of the new millenium. Geneva: WHO, 2003:158. http://search.who.int/search?ie¼utf8&site¼default_collection&client¼WHO&proxystylesheet¼WHO&output¼xml_no_dtd&oe¼utf8&q¼musculoskeletal&Search¼Search (accessed May 2009).

3. Ellis N. Work and health: management in Australia and New Zealand. Melbourne:Oxford University Press, 2001.

4. National Institute for Occupational Safety and Health. Musculoskeletaldisorders and workplace factors. A critical review of epidemiological evidence forwork-related musculoskeletal disorders of the neck, upper extremity and low back.Cincinnati: National Institute for Occupational Safety and Health, 1997.

5. Harcombe H, McBride D, Derrett S, et al. Prevalence and impact of musculoskeletaldisorders in New Zealand nurses, postal workers and office workers. Australian &New Zealand Journal of Public Health 2009;33:437e41.

6. Fransen M, Woodward M, Norton R, et al. Risk factors associated withthe transition from acute to chronic occupational low back pain. Spine2002;27:92e8.

7. Lilley R. The development of an occupational health and safety surveillance tool forNew Zealand workers: PhD Thesis. Department of Preventive and Social Medicine.University of Otago, 2007.

8. Coggan C, Norton R, Roberts I, et al. Prevalence of back pain among nurses. N ZMed J 1994;107:306e8.

9. Fogg T, Henderson R. Upper extremity musculoskeletal strain in a sample of NewZealand clerical workers: an examination of self-reported and diagnosed strain.J Occup Health Safety Aust NZ 1996;12:207e12.

10. Taylor W. Musculoskeletal pain in the adult New Zealand population: prevalenceand impact. NZ Med J 2005. http://www.nzma.orgnz/journal/118-1221/1629/(accessed Aug 2009).

11. Peduzzi P, Concato J, Kemper E, et al. A simulation study of the numberof events per variable in logistic regression analysis. J Clin Epidemiol1996;49:1373e9.

12. Kuorinka I, Jonsson B, Kilbom A, et al. Standardised Nordic questionnaires for theanalysis of musculoskeletal symptoms. Appl Ergon 1987;18:233e7.

13. Palmer KT, Cooper C, Walker-Bone K, et al. Use of keyboards and symptoms in theneck and arm: evidence from a national survey. Occup Med 2001;51:392e5.

14. Smedley J, Inskip H, Trevelyan F, et al. Risk factors for incident neck and shoulderpain in hospital nurses. Occup Environ Med 2003;60:864e9.

15. Bosma H, Marmot M, Hemingway H, et al. Low job control and risk of coronaryheart disease in Whitehall II (prospective cohort) study. BMJ 1997;314:558e65.

16. Derogatis LR, Melisaratos N. The brief symptom inventory: an introductory report.Psychol Med 1983;13:595e605.

17. Veit CT, Ware JE Jr. The structure of psychological distress and well-being ingeneral populations. J Consult Clin Psychol 1983;51:730e42.

18. Schwarzer R. General perceived self-efficacy scale (GSE). http://www.userpage.fu-berlinde/whealth/selfscal.htm (accessed 1 Jul 2006).

19. Brooks R, The Euroqol Group. Euroqol: the current state of play. Health Policy1996;37:53e72.

20. StataCorp. Stata statistical software: release 9. College Station, TX: StatCorp LP,2005.

21. Hoogendoorn WE, van Poppel MNM, Bongers PM, et al. Systematic review ofpsychosocial factors at work and private life as risk factors for back pain. Spine2000;25:2114e25.

22. Yip VY. New low back pain in nurses: work activities, work stress and sedentarylifestyle. J Adv Nurs 2004;46:430e40.

23. Kumar S. Cumulative load as a risk factor for back pain. Spine 1990;15:1311e16.24. Benavides FG, Benach J, Diez-Roux AV, et al. How do types of employment relate

to health indicators? Findings from the second European survey on workingconditions. J Epidemiol Community Health 2000;494e501.

25. Kopec JA, Sayre EC. Work-related psychosocial factors and chronic pain:a prospective cohort study in Canadian workers. J Occup Environ Med2004;46:1263e71.

26. Lipscomb JA, Trinkoff AM, Geiger-Brown J, et al. Work-schedule characteristicsand reported musculoskeletal disorders of registered nurses. Scand J Work EnvironHealth 2002;28:394e401.

27. Waddell G. The back pain revolution. 2nd edn. Edinburgh: Churchill Livingstone,2004.

28. Cole DC, Ibrahim SA, Shannon HS, et al. Work correlates of back problemsand activity restriction due to musculoskeletal disorders in the Canadian nationalpopulation health survey (NPHS) 1994-5 data. Occup Environ Med 2001;58:728e34.

29. Nahit ES, Hunt IM, Lunt M, et al. Effects of psychosocial and individual psychologicalfactors on the onset of musculoskeletal pain: common and site-specific effects. AnnRheum Dis 2003;62:755e60.

30. Ostergren PO, Hanson BS, Balogh I, et al. Incidence of shoulder and neck pain ina working population: effect modification between mechanical and psychosocialexposures at work? Results from a one year follow up of the Malmo shoulder andneck study cohort. J Epidemiol Community Health 2005;59:721e8.

31. Woods V. Work-related musculoskeletal health and social support. Occup Med2005;55:177e89.

32. Andersen JH, Kaergaard A, Mikkelsen S, et al. Risk factors in the onset of neck/shoulder pain in a prospective study of workers in industrial and service companies.Occup Environ Med 2003;60:649e54.

33. Gureje O, Simon GE, Usten TB, et al. Somatization in cross-cultural perspective:a World Health Organization study in primary care. Am J Psychiatry1997;154:989e95.

34. Palmer KT, Calnan M, Wainwright D, et al. Disabling musculoskeletal pain and itsrelation to somatization: a community-based postal survey. Occup Med2005;55:612e17.

35. Issever H, Onen L, Sabuncu H, et al. Personality characteristics, psychologicalsymptoms and anxiety levels of drivers in charge of urban transportation in Istanbul.Occup Med 2002;52:297e303.

36. Macfarlane GJ, Hunt IM, Silman AJ. Role of mechanical and psychosocial factors inthe onset of forearm pain: a prospective population based study. BMJ2000;321:1e5.

37. McBeth J, Macfarlane GJ, Benjamin S, et al. Features of somatization predict theonset of chronic widespread pain: results of a large population-based study. ArthritisRheum 2001;44:940e6.

38. Pincus T, Burton AK, Vogel S, et al. A systematic review of psychological factors aspredictors of chronicity/disability in prospective cohorts of low back pain. Spine2002;27:E109e20.

39. Taylor WJ, Dean SG, Siegert RJ. Differential association of general and healthself-efficacy with disability, health-related quality of life and psychological distressfrom musculoskeletal pain in a cross-sectional general adult population survey. Pain2006;125:225e32.

40. Croft PR, Lewis M, Papageorgiou AC, et al. Risk factors for neck pain: a longitudinalstudy in the general population. Pain 2001;93:317e25.

100 Injury Prevention 2010;16:96e100. doi:10.1136/ip.2009.021766

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nurses, postal workers and office workersmusculoskeletal disorders in New Zealand Physical and psychosocial risk factors for

Helen Harcombe, David McBride, Sarah Derrett and Andrew Gray

doi: 10.1136/ip.2009.0217662010 16: 96-100 Inj Prev 

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