PRESENTATION ON THE DRAFT REPORT OF THE CHAIR OF THE OCCUPATIONAL DISEASE ADVISORY PANEL (ODAP)

BY OHCOW HAMILTON

OHCOW is funded through the prevention division of the WSIB and our mandate is to assist the workplace parties in the prevention of occupational disease and injury.  Our multi-disciplinary team of occupational physicians, nurses, hygienists, ergonomists, and other professionals provide technical support to Joint Health & Safety Committees (JH&SC) to identify the conditions and exposures that may cause occupational disease and injury and provide them with recommendations and tools they can use to reduce or eliminate these risk factors.

We also assist workers in the determination of the work relatedness of their disease or injury and through our investigation have provided evidence to further their claims.

We need to see the WSIB take action on this serious issue and take the proactive steps required to deal with occupational disease in a timely fashion so that the knowledge and the resources can be put to the preventions of occupational disease.

OHCOW Hamilton feels that, overall, the recommendations of the ODAP paper if properly and successfully implemented, could significantly improve the system for all parties concerned.  Having said that, we would hasten to point out that rather than formalizing what is currently practiced by the WSIB, the introduction and adoption of these principles into standard practice would be a significant challenge for the WSIB requiring fundamental restructuring.  Unfortunately, the WSIB has not applied these legal and scientific principles and consequently the WSIB staff does not have the organizational structure to enable them to be applied consistently and successfully.  So, while it may seem the ODAP paper is recommending formalizing the status quo, these principles, in fact, have not been used systematically by the WSIB, and therefore, these recommendations are a significant departure from current practice.

We hope to demonstrate by examples from our experience why we believe this to be the case and also to provide some constructive criticism and suggestions that could make the introduction of these principles possible so they could become part of the WSIB’s operational policy and more importantly practice. 

The ODAP paper describes a process which is investigative rather than adversarial, and the WSIB plays the dual neutral roles of investigator and decision maker.  Unfortunately, the WSIB has not been adequately gathering or evaluating scientific material and the responsibility of providing the WSIB with the evidence (the burden of proof) has fallen to those who represent the worker or the employer.  Presenting information to the WSIB to establish the burden of proof has become competitive, making the process adversarial.  OHCOW is involved in WSIB casework and spends a considerable proportion of its time and resources gathering and evaluating the relevant scientific evidence, while we consider that this work assists the WSIB in the task of investigation, we are often requested to do this after the process identified in the ODAP paper has been deemed to have taken place by the WSIB, clearly showing the process is not in place to do the investigations at the WSIB. If the WSIB adequately fulfilled its obligations under the burden of proof our time and resources would be put to better use in prevention activities aimed at eliminating or controlling the risk factors and conditions that cause or contribute to occupational diseases and injuries.

In many cases particularly of occupational disease it is up to the worker to prove his claim. 

The “decision maker” (adjudicator) identified in the ODAP paper has been given responsibilities that in more complicated cases would very likely be beyond the ability and training of any one person.  Complex cases could best be handled by a well-coordinated team.  No one individual working at the adjudicator level would have the necessary education, training, experience and time necessary to adequately evaluate the breadth of medical and scientific literature involved.  While the decision maker can call upon the opinion of medical and scientific “experts”, there is no requirement for them to do so and where opinion is requested they are not trained to properly evaluate and weigh the quality of the evidence provided.  What passes for expertise at the WSIB is more often the product of opinion than of research. Where expert opinion is sought outside the WSIB, the individual’s area of expertise may not match the needs of the case or the frame of reference of the opinion may not be appropriate. 

There is little value in applying the causation test, the standard of proof, the benefit of doubt and other legal principles where the medical and scientific questions of a case have not been researched adequately and are not well understood. 

The ODAP paper recommends that the WSIB obtain the necessary evidence before making a decision and if that evidence is lacking the decision should be based on what is currently available.  The ODAP paper does not provide a guideline for how evidence is to be gathered or for evaluating and weighing the evidence.  The WSIB decision maker must determine “which way the evidence points” in making a decision but there is no requirement for them to describe how they have gone about this.  What should be an objective decision making process appears to be far too subjective.  Thus the process must be formal and transparent.  Rather than alluding to “the merits and justice” of the case, for this phrase to have any meaning the adjudicator must show in detail how this principle has been applied. 

We bring to the attention of the Chair, the March 1993  “Report of the Occupational Disease Task Force”  and recommendations numbers 38, 39, 40, 41, 42, 43, 44, 45, 46, and 47 (these recommendations provide requirements of training, resources and staffing expertise required, clear guidelines dealing with occupational disease, gathering and weighing of evidence and applying the legal tests to the evidence), and that these recommendations should be the foundation followed in the training and adjudication of occupational disease claims.

Much of the content of the WSIB schedules and policies is historical and has not been revised to reflect current understanding in the medical and scientific literature of occupational disease. Where individual cases are adjudicated it is not possible for the WSIB staff in that department to keep abreast of major advances in the medical and scientific literature of occupational disease.

It is clear that individuals and groups working within the WSIB as well as external experts involved in the same cases may not clearly appreciate one another’s responsibilities.  This has lead to incorrect statements in the expert reports which the adjudicator is obliged to factor into the decision making process.

To illustrate this point, I will use the example of a series of five claims for brain cancer that were recently submitted on behalf of workers from a single work place.  An occupational hygienist reviewed the exposures and in addition to the adjudicator and an epidemiologist, an external medical reviewer and someone form the Medical Occupational Disease Branch (MODB) were involved.  Each worked independently of one another and there was no sign of interaction between them.

The WSIB hygienist submitted a list of chemicals having some association with brain cancer to the workplace parties and asked them whether they had been present at the workplace.  This list was based on a chapter in a review textbook¹ often cited in WSIB documents.  Presumably, the medical reviewer would have produced a more exhaustive list.

The occupational hygienist did some qualitative assessment using a list of hazardous air contaminants which he had compiled from information collected from MOL inspection reports, the firm's process information, co-worker interviews and the literature.  The occupational hygienist states that the report “does not focus on particular agents that may be associated with a particular disease” and “a more specific assessment can be conducted once a disease and possible agents of disease have been identified”.  In fact a more specific assessment has not been reported.  It may not have been conducted because the WSIB has not an adequate review of the occupational brain cancer literature.

The comments of the “Medical Occupational Disease Branch” (MODB) on this file were summarized in a report by a WSIB epidemiologist. From this review, the MODB apparently used the occupational hygienists estimates to suggest that the workers exposures were quantitatively insufficient to have caused cancer and to exclude the possibility of exposures not expressly identified in the occupational hygiene report.  They also stated that these workers were not exposed to “known carcinogens”.  Yet the occupational hygienist specifically stated that his report was qualitative rather than quantitative; it was not an exhaustive list of exposures and the purpose for this was not to identify carcinogens or agents known to cause a specific disease.  In fact among the chemical exposures listed by the occupational hygienist are some very well known IARC carcinogens – asbestos (IARC Group 1), arsenic (IARC Group 1), carbon tetrachloride (IARC Group 2B) and chromium VI (IARC Group 1), to name only a few.

The MODB report as reviewed by the WSIB epidemiologist lacked scientific rigor and legal principle as it contained numerous factual errors, misinterpretations of scientific principles and incorrect characterizations and had been written in such a way as to lead the reader to gain an unfavorable impression of the work being reviewed. From the comments made about the supporting literature suggested by OHCOW, it did not seem that the MODB reviewer had bothered to read the papers or had not understood them.

A neurosurgeon, likely familiar with brain cancer but apparently less familiar with epidemiology was selected to review the epidemiological literature regarding occupational brain cancer.  The sole criterion used in evaluating causality seemed to be absolute certainty or a “direct causal link” rather than the rules of evidence commonly used by toxicologists and epidemiologists.  In addition, it would appear that the medical reviewer relied almost exclusively on secondary sources for information rather than reading the original research reports.  The reviewer ultimately concluded that brain cancer may be caused by “as yet undiscovered environmental factors” despite the many relevant discoveries published in a substantial body of epidemiological literature.

OHCOW had already provided the WSIB with an 80-page table summarizing occupational brain cancer studies that may be relevant to this workplace and group of workers.  This summary table included 131 cohort studies, 8 case-control studies, 15 review papers and a handful of animal studies and case reports.  With this summary, OHCOW also provided a 750-paper bibliography of occupational brain cancer papers.

Appendix C of the ODAP paper proposes guidelines for conducting systematic reviews adapted from the WHO’s 2000 guideline document.  We are aware of only one systematic review by the WSIB, which is a review of stomach cancer in foundry workers.  While there are surely more systematic reviews at the WSIB, they are far too rare.  The evidence-based approach recommended by ODAP would be in direct contrast to the way in which, for example, the brain cancer claims were assessed, as described above.  This evidence-based approach should be extended to all levels of WSIB activity (schedules, policies and individual case work).

The use of criteria to systematically assess the validity of epidemiological studies should be fundamental to any reviewer.  Those developed by Bradford Hill (1965) have been recognized almost universally and have been recommended in the ODAP paper.  The reviews in the brain cancer series described above, particularly those by the medical reviewer and the MODB reviewer would have benefited greatly from the application of these criteria.  To be of real value, these criteria must be applied in a thoughtful manner by individuals having the necessary background (education, training and experience) to do so.  The criteria assumes that a user has a sophisticated grasp of several sciences and medicine including toxicology and epidemiology and well-exercised powers of logic.  Because the WSIB has not been in the practice of using such criteria, there is a danger that by simply adopting their use, they could be misapplied which may be worse than not using them at all.  For instance, all of the criteria may not apply in each case and the reviewer must know which to apply and when and of course, how.  As with the adoption of systematic reviews into the culture of the WSIB, the use of criteria for evaluating and determining causality would necessitate considerable infrastructure and organizational changes within the WSIB.

We will also raise a few other examples to show how the system fails to give justice to workers who have suffered an occupational disease, and discuss why the Board needs to provide timely assistance and compensation to workers who have suffered an occupational disease. 

Shortly after OHCOW opened in 1989, one of the first patients seen in the clinic was an individual with lung cancer who worked in a plant making various abrasive products.  A claim for lung cancer had already been filed with the WCB prior to coming to the clinic and the worker and his representative were looking for a determination and evidence of the work relatedness of his lung cancer.  The claim had been denied by the Board citing there was no evidence that his lung cancer was related to work.  Clinic staff investigated the exposures and the literature and put together documentation to show evidence of a probable cause that his lung cancer was related or caused by his work.  The claim was allowed in 1997, unfortunately the worker died from his illness prior to the claim being allowed. 

Another individual worked in a shoe factory and was exposed to a number of substances such as solvents, adhesives, and dyes, and was diagnosed with scleroderma.  A very similar story as to our previous example showed that once the evidence of exposure and literature were gathered, it showed the work could cause the disease.  The claim was allowed a couple of years ago after being in the system for some 10 years.

The last example is of two people who work for the same employer but in a different location, with exposure to mercury from the same type of process.  Each of these workers has been diagnosed with neurological disorders of a type known to be caused by mercury exposure.  Again, the process of recognizing these as occupational illnesses has taken far too long.  We have learned that one individual’s claim that had been established in 1998, has been accepted. The other claim which was filed in 2001 is still pending. 

Sadly, we can cite numerous similar cases.  In all of these cases, not only have the individuals suffered serious irreversible diseases, but they and their families have also suffered both personal and financial hardships in getting the Board to recognize their occupational disease.

In March 1993, the Occupational Disease Task Force submitted their report to the Minister of Labour with 54 recommendations “directed to improving the present system for adjudication of occupational disease.  Many may be considered to be short-term solutions and others as initiating moves towards the only long term solution:  “Prevention”. 

When one reviews the recommendations of the Occupational Disease Task Force report in 1993 and the document of the ODAP, we see that many of the same issues are still in discussion on how these will be resolved.  When we add to this, documents/articles by Ison in 1989 on, “Compensation for Industrial Disease under the Workers Compensation Act of Ontario” and Spiegel and Yassi in 1991 on developing “Occupational Disease Surveillance in Canada:   A Framework for Considering Options and Opportunities”, it is clear that it is time that talking and discussion papers and reports must end.  We need action on these issues so that we can begin the real process that is required, the prevention of occupational disease. 

1. Schottenfeld D., Fraumeni J.F.(editors).  Cancer Epidemiology and Prevention.  Oxford University Press, New York; 1996