Impact of expert versus measurement-based occupational noise exposure estimates on exposure-response relationships

  • Melissa C. Friesen
  • Hugh W. Davies
  • Aleck Ostry
  • Kay Teschke
  • Paul A. Demers
Original Article

Abstract

Objective

Expert-judgment has frequently been used to assess quantitative exposure for epidemiologic studies, but accuracy varies widely dependent on the type of exposure and the availability of measurements to anchor estimates. There is limited empirical evidence of the sensitivity of exposure-response relationships to expert- versus measurement-based exposure assessment strategies. We examined the sensitivity of the exposure-response relationship between occupational noise exposure and acute myocardial infarction (AMI) mortality using both expert- and measurement-based occupational noise estimates in a retrospective cohort study of sawmill workers (n = 27,499).

Methods

Expert-based noise estimates were evaluated by four industry experts who rated 54 sawmill jobs on a four-point scale. Measurement-based noise estimates were derived from statistical models that accounted for job, mill, and time period differences. The model-based estimates were adjusted to account for the use of hearing protective devices (HPD). We examined the shape, goodness of fit, precision, and expected versus observed attenuation of the exposure-response relationships between cumulative noise exposure and AMI mortality (910 deaths).

Results

The correlations between the expert-based and the measurement-based unadjusted and HPD-adjusted cumulative noise estimates were 0.81 and 0.57, respectively. The HPD-adjusted model-based estimates provided the most precise exposure-response relationship; no associations were observed with the unadjusted or expert-based noise estimates. In a subgroup with minimal HPD use (n = 8,700, 520 deaths), the expert- and model-based noise estimates resulted in similar relative risks; the model-based approach was 12% more precise.

Conclusion

The measurement-based approach was more precise, as expected, but experts were reasonably able to rank occupational noise exposures. The experts’ assessment was, however, unable to account for HPD use, which made a substantial contribution to exposure misclassification in this study. The experts’ noise estimates would be more useful for risk assessment if they were calibrated against units of noise exposure.

Notes

Acknowledgments

This research was funded by Canadian Institutes for Health Research, BC Lung Association, US National Institute for Occupational Safety and Health. Trainee support for MF was provided by the Michael Smith Foundation for Health Research and the Canadian Institutes for Health Research.

References

  1. Astrakianakis G, Band PR, Le N, Bert J, Janssen B, Svirchev LM, Tang C, Anderson J, Keefe A (1998) Validation of a mill-specific job-exposure matrix in the British Columbia pulp and paper industry. Appl Occup Environ Hyg 13:1–7Google Scholar
  2. Babisch W (1998) Epidemiological studies of the cardiovascular effects of noise—a critical appraisal. Noise Health 1:24–39PubMedGoogle Scholar
  3. Bjorntorp P (1997) Stress and cardiovascular disease. Acta Physiol Scand Suppl 640:144–148PubMedGoogle Scholar
  4. Davies HW (2002) Exposure to occupational noise and risk of cardiovascular disease: a retrospective cohort study. Interdisciplinary Studies. PhD thesis, Vancouver, University of British Columbia Google Scholar
  5. Davies HW, Teschke K, Kennedy SM, Hodgson MR, Hertzman C, Demers PA (2005) Occupational exposure to noise and mortality from acute myocardial infarction. Epidemiol 16:25–32CrossRefGoogle Scholar
  6. de Cock J, Kromhout H, Heederik D, Burema J (1996) Experts' subjective assessment of pesticide exposure in fruit growing. Scand J Work Environ Health 22:425–432PubMedGoogle Scholar
  7. Hertzman C, Teschke K, Dimich-Ward H, Ostry A (1988) Validity and reliability of a method for retrospective evaluation of chlorophenate exposure in the lumber industry. Am J Ind Med 14:703–713PubMedCrossRefGoogle Scholar
  8. Hertzman C, Teschke K, Ostry A, Hershler R, Dimich-Ward H, Kelly S, Spinelli JJ, Gallagher RP, McBride M, Marion SA (1997) Mortality and cancer incidence among sawmill workers exposed to chlorophenate wood preservatives. Am J Public Health 87:71–79PubMedCrossRefGoogle Scholar
  9. Ising H, Babisch W, Kruppa B, Lindthammer A, Wiens D (1997) Subjective work noise: a major risk factor in myocardial infarction. Soz Praventivmed 42:216–222PubMedCrossRefGoogle Scholar
  10. Kromhout H, Oostendorp Y, Heederik D, Boleij JS (1987) Agreement between qualitative exposure estimates and quantitative exposure measurements. Am J Ind Med 12:551–562PubMedCrossRefGoogle Scholar
  11. Lees R, Romeril C, Wetherall L (1980) A study of stress indicators in workers exposed to industrial noise. Can J Public Health 71:261–265PubMedGoogle Scholar
  12. Ostry A (1998). Psychosocial job strain and coronary heart disease in a cohort of blue collar workers. Department of Health Care and Epidemiology. PhD thesis, Vancouver, University of British ColumbiaGoogle Scholar
  13. Ostry AS, Marion SA, Demers PA, Hershler R, Kelly S, Teschke K, Mustard C, Hertzman C (2001) Comparison of expert-rater methods for assessing psychosocial job strain. Scand J Work Environ Health 27:70–75PubMedGoogle Scholar
  14. Richardson DB, Loomis D (2004) The impact of exposure categorisation for grouped analyses of cohort data. Occup Environ Med 61:930–935PubMedCrossRefGoogle Scholar
  15. Seixas N, Neitzel R, Sheppard L, Goldman B (2005) Alternative metrics for noise exposure among construction workers. Ann Occup Hyg 49:493–502PubMedCrossRefGoogle Scholar
  16. Stewart PA, Herrick RF (1991) Issues in performing retrospective exposure assessment. Appl Occup Environ Hyg 6:421–427Google Scholar
  17. Teschke K, Olshan AF, Daniels JL, De Roos AJ, Parks CG, Schulz M, Vaughan TL (2002) Occupational exposure assessment in case-control studies: opportunities for improvement. Occup Environ Med 59:575–593PubMedCrossRefGoogle Scholar
  18. Teschke K, Ostry A, Hertzman C, Demers PA, Barroetavena MC, Davies HW, Dimich-Ward H, Heacock H, Marion SA (1998) Opportunities for a broader understanding of work and health: Multiple uses of an occupational cohort database. Can J Public Health 89:132–136PubMedGoogle Scholar
  19. Theriault G, Tremblay C, Armstrong B (1988) Risk of ischemic heart disease among primary aluminum production workers. Am J Ind Med 13:659–666PubMedCrossRefGoogle Scholar

Copyright information

© Springer-Verlag 2007

Authors and Affiliations

  • Melissa C. Friesen
    • 1
  • Hugh W. Davies
    • 1
  • Aleck Ostry
    • 2
  • Kay Teschke
    • 1
    • 2
  • Paul A. Demers
    • 1
    • 2
  1. 1.School of Occupational and Environmental HygieneUniversity of British ColumbiaVancouverCanada
  2. 2.Department of Health Care and EpidemiologyUniversity of British ColumbiaVancouverCanada

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