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

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. Electronic supplementary material The online version of this article (10.1186/s12940-019-0451-0) contains supplementary material, which is available to authorized users.

Retrospective Exposure Assessment Methods Used in Occupational Human Health Risk Assessment: A Systematic Review

“…Moreover, the odds ratios (ODs) were used by Mester and collaborators [ 39 ] to evaluate the level of disagreement between different ratings of exposure. Other statistical techniques, such as linear regression models [ 55 ], least-square linear regression analysis for the evaluation of data collected from personal and area samplings [ 54 ], Bayesian hierarchical models [ 50 ] and weighted Cohen’s Kappa with linear weights [ 36 ] as well as Structural Equation Modelling Techniques (SEM) for predicting shifts in the exposure [ 24 ] were used. For the evaluation of models, methods such as Cross-validation of the modelling process were applied using data splitting and Monte Carlo techniques [ 34 ].…”

Occupational exposure to polycyclic aromatic hydrocarbons and risk of prostate cancer

“…This has long been considered to be the reference approach for community-based retrospective studies [ 37 , 38 ]. We further improved on the transparency of the coding by applying a hybrid approach to guide the experts [ 23 ]. PAHs exposures were studied together as well as according to their material source, thereby capturing more specific exposure circumstances.…”

“…The hybrid expert-based assessment approach, described previously [ 23 ], was used to assign exposures based on the 16,065 detailed job descriptions. By providing clearer guidelines for coding, the hybrid expert-based approach was recently developed to improve on efficiency, comprehensiveness and transparency of assignments, and greater coherence between experts [ 23 ].…”

“…The hybrid expert-based assessment approach, described previously [ 23 ], was used to assign exposures based on the 16,065 detailed job descriptions. By providing clearer guidelines for coding, the hybrid expert-based approach was recently developed to improve on efficiency, comprehensiveness and transparency of assignments, and greater coherence between experts [ 23 ]. Basically, it makes use of job-exposure profiles summarizing expert evaluations from previous studies, complemented with comments on coding specific exposure circumstances, which together with the subjects’ job descriptions, guide experts in their assignments.…”

Applying two general population job exposure matrices to predict incident carpal tunnel syndrome: A cross-national approach to improve estimation of workplace physical exposures

“…Differences in constructs between general population JEM provide an opportunity to combine complementary variables into a single multivariable model. Hybrid exposure assessment methods have been used to study prostate cancer risk (30) and shoulder disorders (1). Since the development of MSD is multifactorial (31), relying on a single source of exposure information may not provide the optimal breadth of physical exposure data, and hybrid exposure methods offer the opportunity to improve precision while maintaining the efficiency of a JEM.…”