title: Physical workload and ergonomic factors associated with prevalence of back and neck pain in urban transit operators.
abstract: METHODS
  Back and neck pain was studied cross-sectionally in 1,449 urban transit drivers by linking medical data, self-reported ergonomic factors, and company records on job history.
  
  
  OBJECTIVE
  The goal was to examine the relation between physical workload, ergonomic factors, and the prevalence of back and neck pain.
  
  
  BACKGROUND
  Researchers, to date, have not found an independent effect of ergonomic factors on back and neck pain while accounting for the effects of past and current physical workload.
  
  
  METHODS
  Self-reported ergonomic factors, vehicle type, physical workload (measured as duration of driving), height, weight, age, and gender were analyzed in relation to back and neck pain, using multivariable logistic regression models.
  
  
  RESULTS
  Physical workload showed a positive dose-response relation with back and neck pain after controlling for vehicle type, height, weight, age, and gender. The odds ratio for 10 years of driving was 3.43. Additional adjustment for ergonomic factors decreased this odds ratio to 2.55. Six out of seven ergonomic factors were significantly related to the prevalence of back and neck pain after adjustment for age, gender, height, weight, and physical workload. Problems with adjusting the seat had the largest effect (odds ratio = 3.52). Women had back and neck pain twice as frequently as men.
  
  
  CONCLUSIONS
  The results support the hypothesis of a causal role of physical workload for the development of back and neck pain. Ergonomic factors partially mediated the risk of back and neck pain associated with driving, suggesting a potential for prevention of back and neck pain by ergonomic redesign of transit vehicles. Elevated risks for back and neck pain for female drivers were not explained by anthropometric and ergonomic factors.
authors.affiliation: Division of Epidemiology, School of Public Health, University of California, Berkeley, USA.
authors.forename: N
authors.initials: N
authors.lastname: Krause
authors.forename: D R
authors.initials: DR
authors.lastname: Ragland
authors.forename: B A
authors.initials: BA
authors.lastname: Greiner
authors.forename: J M
authors.initials: JM
authors.lastname: Fisher
authors.forename: B L
authors.initials: BL
authors.lastname: Holman
authors.forename: S
authors.initials: S
authors.lastname: Selvin
mesh_terms: D000328:Adult; D001334:Automobile Driving; D001824:Body Constitution; D003430:Cross-Sectional Studies; D003710:Demography; D006804:Ergonomics; D005260:Female; D006801:Humans; D017116:Low Back Pain / Q000453:epidemiology* / Q000209:etiology; D008297:Male; D008875:Middle Aged; D019547:Neck Pain / Q000453:epidemiology* / Q000209:etiology; D009784:Occupational Diseases / Q000453:epidemiology* / Q000209:etiology; D015995:Prevalence; D012307:Risk Factors; D012495:San Francisco / Q000453:epidemiology; D011795:Surveys and Questionnaires; D016526:Workload