The Appeal CommissionThe Workers Compensation Act of Manitoba

Preamble

The worker’s estate appealed the Workers Compensation Board ("WCB") decision that the worker’s permanent partial impairment rating of 20% should be reduced by 50% due to pre-existing and co-existing conditions. A file review took place on March 26, 2025 to consider the worker's appeal.

Issue

Whether or not the worker’s permanent partial impairment rating of 20% should be reduced by 50% due to pre-existing and co-existing conditions.

Decision

The permanent partial impairment rating of 20% should not be reduced by 50% due to pre-existing and co-existing conditions.

Background

The WCB accepted the worker’s claims for injuries sustained as a result of accidents arising out of and in the course of their employment in 1984 and 1993.

The Appeal Commission, in Decision No. 152/19, delivered December 20, 2019, determined the worker was entitled to benefits in relation to a psychological condition arising out of those accidents and noted the worker was first diagnosed with Post Traumatic Stress Disorder (“PTSD”) by the treating psychologist in a report dated March 29, 2017. Later, the WCB determined it was appropriate to use March 29, 2017 as the date of accident for the worker's psychological condition. The WCB also later determined that the worker may be entitled to a permanent partial impairment (“PPI”) award, in relation to the diagnosis of PTSD, but the PPI examination did not occur before the worker’s death on June 30, 2022. In the circumstances, the WCB determined to gather information from the worker’s spouse and the medical reporting to assess the extent of the worker’s impairment due to their psychological condition. A WCB psychiatric consultant met with the worker’s spouse to undertake the PPI assessment on October 4, 2022. Based on that assessment and claim file information as to the worker’s mental health symptoms and functioning prior to their passing, the WCB psychiatric consultant concluded the worker’s PPI rating with respect to the psychological injury was 20%. The WCB consultant noted the worker’s “significant marijuana use” likely contributed to their impairment, but after discussion with the WCB’s Chief Medical Officer, concluded the worker’s PPI rating would not be reduced by 50% due to a pre-existing or co-existing condition. On November 14, 2022, the WCB advised the worker's estate of the PPI rating of 20%.

On October 8, 2024, Review Office determined the worker’s permanent partial impairment rating and award was not correct and that the permanent partial impairment rating of 20% should be reduced by 50% due to co-existing and pre-existing conditions.

The worker’s representative filed an appeal to the Appeal Commission on January 30, 2025 and a file review was arranged.

Reasons

Applicable Legislation and Policy

The provisions of The Workers Compensation Act (the “Act”) in effect as of the date of the accident are applicable to the worker’s appeal. The Act provides in s 4(1) that compensation is payable when a worker sustains personal injury by accident arising out of and in the course of the employment. Section 37 of the Act outlines that compensation under the Act includes an impairment award. Section 38 of the Act provides that the WCB “…shall determine the degree of a worker's impairment expressed as a percentage of total impairment” and pay the worker a lump sum impairment award calculated as set out in s 38(2).

The WCB’s Policy 44.90.10, Permanent Impairment Rating (the "PPI Policy”) describes how permanent impairment ratings are calculated. The Policy provides that the degree of impairment will be established by the WCB's Healthcare Services Department in accordance with the Policy, and that whenever possible and reasonable, impairment ratings will be established strictly in accordance with Schedule A to the Policy. The PPI Policy also provides that if a worker has a pre-existing condition and has an impairment, the worker is eligible for a PPI rating based on the difference between the total rating and the rating assigned to the pre-existing condition, which is determined based on the best information possible.

Schedule A to the PPI Policy outlines the process by which the degree of permanent impairment from a workplace injury should be evaluated. Impairment rating of psychological function is determined through clinical examination or assessment of the medical information on file, in accordance with the specified scales outlined in the Schedule, when practical. The Schedule provides that: “The existence of a pre-existing mental health condition will not negate an injured worker’s entitlement to an impairment rating arising from a WCB accepted mental health diagnosis” and that “When evaluating impairment associated with a mental health condition, the examiner is obligated to consider what portion of the impairment is due to the WCB accepted mental health diagnosis versus the portion attributable to a pre-existing mental health condition.” Schedule A outlines that the WCB will assign a rating to the pre-existing mental health condition based on the best information available, following the Schedule when practical or if not possible, assigning a rating of 0% impairment to the pre-existing mental health condition if determined to be minor or 50% impairment if determined to be major. The Schedule further provides that a pre-existing condition is major for the purpose of impairment rating if:

• The current impairment of psychological function was/is significantly affected by the pre-existing condition; or 

• The WCB has determined that the workplace injury enhanced the pre-existing condition; or 

• The WCB has determined that the pre-existing condition contributed to the workplace injury.

The presence of a co-existing condition will be treated the same as a pre-existing condition for the purpose of the PPI determination.

Position of Worker’s Estate

A worker advisor represented the worker’s estate in this appeal and provided a written submission on March 18, 2025 for the panel’s consideration.

The position of the worker’s estate is that the worker’s pre-existing physical health conditions should not be considered in any determination of whether the worker has a pre-existing mental health condition as this is contrary to the express provisions of Schedule A of the PPI Policy.

Further, the estate submits that while other psychological conditions were queried or diagnosed prior to the diagnosis of PTSD, after that diagnosis was provided there is little information in the medical reporting as to the presence of any other psychological conditions.

In relation to the question of the worker’s cannabis use, the estate submits that the evidence does not confirm a diagnosis of any disorder in relation to that usage, which was prescribed to treat the worker’s PTSD and used at levels consistent with or less than the prescribed amounts.

The worker’s estate relies on the assessment of the worker’s impairment rating provided by the WCB psychiatric consultant with the support of the WCB’s chief medical officer, who concluded that the evidence did not support the conclusion that the worker had a major pre-existing condition, and as such there should be no reduction to the assessed PPI rating of 20% under the provisions of the PPI Policy.

Employer’s Position

The employer’s workers compensation coordinator represented the employer in this appeal and relied on a written submission provided on March 19, 2025 for the panel’s consideration.

The employer’s position is that the WCB correctly determined that the worker’s PPI rating of 20% should be reduced by 50% due to their pre-existing and co-existing conditions. The employer’s representative submitted that the position of the WCB psychiatric consultant is incorrect in determining that the worker’s impairment was all related to the workplace incident noting the evidence of other pre-existing and co-existing factors, and that the PPI Policy does not allow for discretion in considering the potential impact of any pre-existing and co-existing factors. The employer’s representative noted that in various specific domains of assessment, there were other medical issues contributing to the worker’s impairment which should be considered.

The employer’s representative also noted the WCB psychiatric consultant’s comment as to the likely significant impact of the worker’s marijuana use, which would support a finding that the worker had a major pre-existing or co-existing condition.

Analysis

This appeal considers whether the WCB correctly reduced the PPI rating of 20% calculated in relation to the worker’s compensable psychological condition by 50% on the basis that the worker had major pre-existing and co-existing conditions. For the appeal to succeed, the panel would have to determine that the evidence does not support a finding that the worker had major pre-existing and/or co-existing conditions and therefore the PPI rating should not be reduced by 50%. As detailed in the reasons that follow, the panel finds that the worker’s PPI rating should not be reduced by 50% as the evidence does not support a finding that the worker had such a condition or conditions.

In considering the evidence, the panel finds no fault in the process by which the WCB psychiatric consultant assessed the worker’s PPI rating in relation to their compensable psychological condition. Based on the October 4, 2022 report of the WCB psychiatric consultant, the panel is satisfied that the WCB undertook the appropriate measures and processes in its assessment of the degree of the worker’s impairment, based on a combination of an in-person discussion with the worker’s surviving spouse and relevant file documents. We note the WCB psychiatric consultant assessed the worker’s Global Assessment of Functioning (“GAF”) score and their Psychiatric Impairment Rating (“PIRS”) score, both as required by Schedule A. The psychiatric consultant explained they did not complete the Brief Psychiatric Rating Scale (“BPRS”) because this can only be determined by a mental status examination of the individual and cannot be retrospectively scored based on the report of a family member. Based on the GAP score of 20% (based on a score between 31-40 which corresponds to 20% per Table 20-3) and PIRS score of 20% (based on a score of 6 which corresponds to 20% per Table 20-10), the WCB psychiatric consultant determined, based on the final rating process set out in Table 20-11, that the worker’s PPI rating was 20%. The panel noted that the PPI Policy only requires that the WCB establish impairment ratings “strictly in accordance with…Schedule A” when it is possible and reasonable to do so. In this case, given the worker’s untimely passing, it was not possible or reasonable to strictly comply with the process set out in Schedule A; nonetheless, the WCB applied those aspects of the assessment process that could be determined based on the available information, relying on both the interview with the surviving spouse and the most contemporaneous medical reporting. We are satisfied with the process undertaken in these specific circumstances.

The question of whether the worker’s PPI rating should be reduced due to a pre-existing or co-existing mental health condition presupposes that the evidence supports the existence of such a diagnosis, but in this case, the evidence does not lead to such a conclusion. While other psychological diagnoses are considered in the medical reporting, once the diagnosis of PTSD was determined, the other psychological diagnoses are no longer under consideration. There is some later discussion of a possible diagnosis of cannabis use disorder, but this is never confirmed. The panel is satisfied that the evidence confirms the worker had a medical history that included a number of diagnoses that impacted their physical health, but the evidence does not support a finding that the worker had any pre-existing or co-existing mental health condition, which is the relevant determination according to Schedule A of the PPI Policy.

We note that the WCB psychiatric advisor specifically considered whether the evidence supported a reduction in the impairment rating of 20% on the basis of a major pre-existing or co-existing condition, commenting specifically on the worker’s “significant marijuana use” and that this “most likely contributed to [their] impairment significantly” but that based on discussion with the WCB Chief Medical Officer, the psychiatric advisor did not recommend any related reduction in the worker’s impairment rating. The panel further noted that while Review Office disregarded the WCB psychiatric advisor’s conclusion on this point, it did not identify any evidence to support another conclusion, other than pointing to the impact of the worker’s “many co-existing and pre-existing mental and physical ailments, which directly affected the outcome scores of several domains or measurements.” The panel disagrees with the Review Office approach in this regard. The impact of the worker’s co-existing and pre-existing physical health conditions on the scoring in each of the psychological domains and measures outlined in Schedule A is not relevant to the subsequent determination of whether or not there is a major pre-existing or co-existing mental health condition, as outlined in that Schedule. On our review of the evidence, the panel noted varying opinions on the worker’s use of marijuana, whether there was a cannabis use disorder, and the impact of that usage on their PTSD; however, there is also evidence that the worker’s treatment providers prescribed medical marijuana to treat and manage the worker’s compensable PTSD symptoms. We noted the WCB declined to cover this prescription and refused to support any other treatment for the worker’s psychological condition while they continued to use cannabis and certain other medications prescribed to address their psychological condition but find that this is also not relevant to the present question.

Based on the evidence and on the standard of a balance of probabilities, the panel is not satisfied that the evidence supports a finding that the worker had a pre-existing or co-existing mental health condition or that if they did, that it was major, as defined in the PPI Policy. For this reason, the panel concludes that the WCB did not correctly reduce the PPI rating of 20% calculated in relation to the worker’s compensable psychological condition by 50% on the basis that the worker had major pre-existing and co-existing conditions. Therefore, the permanent partial impairment rating of 20% should not be reduced by 50% due to pre-existing and co-existing conditions and the appeal is granted.

Panel Members

K. Dyck, Presiding Officer
J. Peterson, Commissioner
M. Kernaghan, Commissioner

Recording Secretary, J. Lee

K. Dyck - Presiding Officer
(on behalf of the panel)

Signed at Winnipeg this 11th day of April, 2025