title: Predicting work-related incidence of lateral and medial epicondylitis using the strain index.
abstract: BACKGROUND
  The Strain Index (SI) has been developed to evaluate the risk for developing a distal upper extremity disorder. The objective of this study is to determine if the SI predicts incidence cases of work-related lateral, medial, or any epicondylities (LEPI, MEPI, and EPI).
  
  
  METHODS
  Six hundred seven workers were followed for up to 3.5 years, 70 developed EPI on the dominant side (44 LEPI, 13 MEPI, and 13 both). Survival analyses were conducted adjusting for demographic, psychosocial, and work organizational factors, with the SI as time-dependent variable.
  
  
  RESULTS
  High exposure (SI > 5), older age, and self-perceived poor general health were associated with incidence of LEPI and EPI, but not MEPI. There was a significant relationship between higher scores of SI and LEPI, hazard ratio (HR) 2.00 (95% CI 1.04-3.87) for SI 5.1-12, HR 2.12 (95% CI 1.11-4.05) for SI > 12.
  
  
  CONCLUSIONS
  The SI can effectively identify jobs with increased risk of developing incidence of LEPI.
authors.affiliation: Washington Traffic Safety Commission, Olympia, Washington.
authors.forename: Z Joyce
authors.initials: ZJ
authors.lastname: Fan
authors.forename: Stephen
authors.initials: S
authors.lastname: Bao
authors.forename: Barbara A
authors.initials: BA
authors.lastname: Silverstein
authors.forename: Ninica L
authors.initials: NL
authors.lastname: Howard
authors.forename: Caroline K
authors.initials: CK
authors.lastname: Smith
authors.forename: Dave K
authors.initials: DK
authors.lastname: Bonauto
mesh_terms: D006801:Humans; D015994:Incidence; D007588:Job Satisfaction; D009784:Occupational Diseases / Q000175:diagnosis / Q000453:epidemiology*; D011446:Prospective Studies; D012944:Social Support; D013314:Stress, Mechanical; D013716:Tennis Elbow / Q000175:diagnosis / Q000453:epidemiology*
keywords: epicondylitis; incidence; occupation; prospective study; strain index