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. 2019 Feb 15;18(1):14.
doi: 10.1186/s12940-019-0451-0.

A hybrid expert approach for retrospective assessment of occupational exposures in a population-based case-control study of cancer

Jean-François Sauvé  1   2   3 , Jérôme Lavoué  1   2 , Louise Nadon  3 , Ramzan Lakhani  3 , Mounia Senhaji Rhazi  3 , Robert Bourbonnais  3 , Hugues Richard  3 , Marie-Élise Parent  4   5   6
Affiliations

A hybrid expert approach for retrospective assessment of occupational exposures in a population-based case-control study of cancer

Jean-François Sauvé et al. Environ Health. .

Abstract

Background: While the expert-based occupational exposure assessment approach has been considered the reference method for retrospective population-based studies, its implementation in large study samples has become prohibitive. To facilitate its application and improve upon it we developed, in the context of a Montreal population-based study of prostate cancer (PROtEuS), a hybrid approach combining job-exposure profiles (JEPs) summarizing expert evaluations from previous studies and expert review. We aim to describe the hybrid expert method and its impacts on the exposures assigned in PROtEuS compared to those from a previous study coded using the traditional expert method.

Methods: Applying the hybrid approach, experts evaluated semi-quantitative levels of confidence, concentration and frequency of exposure to 313 agents for 16,065 jobs held by 4005 subjects in PROtEuS. These assessments were compared to those from a different set of jobs coded in an earlier study of lung cancer, conducted on the same study base, for 90 blue-collar occupations and 203 agents. Endpoints evaluated included differences in the number of exposures and in the distribution of ratings across jobs, and the within-occupation variability in exposure.

Results: Compared to jobs from the lung cancer study, jobs in PROtEuS had on average 0.3 more exposures. PROtEuS exposures were more often assigned definite confidence ratings, but concentration and frequency levels tended to be lower. The within-occupation variability in ratings assigned to jobs were lower in PROtEuS jobs for all metrics. This was particularly evident for concentration, although considerable variability remained with over 40% of occupation/agent cells in PROtEuS exposed at different levels. The hybrid approach reduced coding time by half, compared to the traditional expert assessment.

Conclusions: The new hybrid expert approach improved on efficiency and transparency, and resulted in greater confidence in assessments, compared to the traditional expert method applied in an earlier study involving a similar set of jobs. Assigned ratings were more homogeneous with the hybrid approach, possibly reflecting clearer guidelines for coding, greater coherence between experts and/or reliance on summaries of past assessments. Nevertheless, significant within-occupation variability remained with the hybrid approach, suggesting that experts took into account job-specific factors in their assessments.

Keywords: Expert assessment; Occupational exposures; Population-based studies; Retrospective exposure assessment.

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Conflict of interest statement

Ethics approval and consent to participate

Ethical approval for the three case-control studies providing the exposure data was obtained from the participating hospitals and from the Institut National de la Recherche Scientifique. All participants provided informed consent.

Consent for publication

All authors read and approved the manuscript.

Competing interests

The authors declare no competing interests.

Publisher’s Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Figures

Fig. 1
Fig. 1
Data selection steps for JEP development and for the between-study comparisons
Fig. 2
Fig. 2
Subset of the JEP for Combination welders (CCDO 8335–126) for 5 agents
Fig. 3
Fig. 3
Relative distributions of the exposures assigned to jobs by categorical exposure metric between studies. OR: Cumulative odds ratio for the odds of a job exposed at higher level categories (eg., definite confidence) relative to lower level categories (eg., possible or probable confidence). CI: Confidence interval
Fig. 4
Fig. 4
Relative proportions of jobs in the most frequently-assigned rating across concordant exposed cells by study and metric
See this image and copyright information in PMC

References

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