California: Bullet Proof Your “Substantial Medical Evidence”

By Hon. Colleen Casey, Former Commissioner, California Workers’ Compensation Appeals Board

“Substantial Medical Evidence” is a ubiquitous catch-all phrase. When does it exist? When is it required for a legal determination? There’s even controversy over what type of medical report might be given more weight than a similarly situated report, even if both are considered “substantial medical evidence.” So how does a litigant ensure compliance? It’s sort of like in 1964, when Supreme Court Justice Stewart attempted a definition of pornography as, “Well, I know it when I see it.” To give the community more concrete guidance, several Noteworthy Panel Decisions (NPD) have issued recently that provide answers as set forth below, to these complicated but critical questions.

1. “Substantial Medical Evidence” May Be Required to Prove “COE”

A finding of industrial causation is usually composed of two elements. (See California Supreme Court case of LaTourette v. WCAB (1998) 17 Cal. 4th 764, 63 Cal. Comp. Cases 253.)

a. Does the injury “arise out of employment” (AOE)? This is a medical issue. Did the physician establish a causal connection between the worker’s employment and the injury?

b. Did the injury “occur in the course of employment” (COE)? This is usually a legal issue. Did the WCJ adequately decide whether the injury occurred within the time, place and circumstances of applicant’s employment?

In the NPD of Hagan v. City of San Bernardino, 2023 Cal. Wrk. Comp. P.D. LEXIS 374, the WCAB challenged the strictures of this paradigm when a psychiatric injury was involved. Here’s what happened.

On 9/18/2022, a call came in over Officer Hagan’s police radio that a motorcycle accident was blocking traffic five miles from his post at the San Bernardino airport. Fearing his girlfriend might be involved, Officer Hagan left his post, with his supervisor’s permission, to investigate.

When he arrived at the scene, he found his girlfriend, a victim of the accident, in a life-threatening situation. Several weeks later, Officer Hagan filed a claim for a psychiatric injury because of this incident. The Qualified Medical Evaluator’s (QME’s) report did find a causal connection between the employment and the injury. Thus, applicant met his burden of proving AOE. Since COE is a “legal issue,” the WCJ did not require an examining physician to weigh in on this. Instead, the WCJ reviewed the evidence and decided Officer Hagan was on a personal errand at the time of the injury. He subsequently issued a “take nothing.”

Upon Reconsideration of this case, the WCAB took issue with a critical question regarding the analysis of COE. At what time, place and circumstance did applicant’s psychiatric injury begin? The WCJ had issued a decision on “when” the psychiatric injury occurred, with no substantial evidence (medical or otherwise) to back it up.

No one had asked the QME these critical questions: Did the injury occur when Officer Hagan first received word of the accident on his dispatch radio and knew his girlfriend could have been involved? Or, was it later, when the ER physician at the hospital told applicant that his girlfriend would likely not survive the night? If the former, a finding of COE might be likely. If the latter, maybe not. Although COE is usually a legal issue for the WCJ to decide, in order to pinpoint the exact time when the psychiatric injury occurred, “substantial medical evidence” was required.

Based on the above, the WCAB vacated the WCJ’s “Take Nothing Order” and held that “Substantial medical evidence” was required to determine whether the psychiatric injury occurred in the course of employment. The matter was returned to the trial level to develop the medical record.

2. Raters of PD May Be Experts, But They Are Not Medical Evaluators

Per the WCAB en banc, Blackledge v. Bank of America (2010) 75 Cal. Comp. Cases 613, only evaluating physicians are eligible to create “substantial medical evidence” to define factors for rating whole person impairments (WPI) of injured workers.

In the case of Nee v. City of LA, 2024 Cal. Wrk. Comp. P.D. LEXIS 197, the Agreed Medical Evaluator (AME) incorrectly used the Range of Motion (ROM) method to determine the Whole Person Impairment (WPI) for applicant’s injury. The lay rater testified at trial that the Diagnostic Related Estimate (DRE) method (and not the ROM method used by the AME) was the correct method to be used in this case as follows:

“Per page 380 [of the AMA Guides], specific criteria must exist to use the ROM method. To apply the ROM method the following criteria must be met, two or more levels of: 1. Fracture. 2. Fusion or loss of motion segment integrity 3. Verified Radiculopathy 4. Any of the above occurring at a single level on two DOI.

The notes then state none are present. No fracture, fusion, or any verified radiculopathy. Not even a single level of radiculopathy. Not only is the ROM method not proper for rating in this case, but it is also not proper to use even DRE Category III.

It is DRE category II with a pain add on that is the proper method of rating this case pursuant to the criteria set forth in the AMA Guides.”

The Workers’ Compensation Arbitrator (WCA) relied on the lay rater’s analysis upon which to base the WPI rating. Although the lay rater may have been correct, it is not acceptable for a WCA to adopt a lay rater’s or even a Disability Evaluator Unit (DEU) rater’s analysis without a foundation of “substantial medical evidence.” This is something only an evaluating physician can provide.

The WCAB rescinded the WCA’s decision and returned the matter to the WCA with the following instructions:

“In the further proceedings, to the extent possible, the evaluating physician should rate applicant's permanent impairment under both the DRE method and the ROM method. The evaluating physician should then determine the appropriate method of assessment explaining the decision with reference to the criteria set forth in the AMA Guides. (AMA Guides, ¶¶ 15.2, 15.8, pp. 379–381, 398.) The evaluating physician should also explain whether a pain add on is appropriate under either or both methods.”

3. Is the Vintage Concept of “Range of Evidence” Still an Option?

Maybe so. Maybe no. According to the NPD of Massia v. R.J. Donovan Correctional Facility, 2024 Cal. Wrk. Comp. P.D. LEXIS 165, the WCJ was not given sufficient “substantial medical evidence” at trial, upon which to base a permanent disability (PD) determination. So he did what he thought was the next best thing. He issued a PD finding based on the “range of evidence.” Upon Reconsideration, the commissioners disagreed with his decision as follows:

“A ‘range of evidence’ approach is more frequently associated with older cases, when parties obtained competing QMEs and each QME's report constituted substantial evidence, which then formed a range from which the WCJ could decide…Today, range of evidence is not often used, but remains permissible when deciding between competing reports, both of which constitute substantial medical evidence. ‘Range of evidence’ cannot be used merely to achieve equity, no matter how noble a goal that may be.”

The WCAB returned the case to the WCJ and instructed him to issue a finding based on “substantial medical evidence” from a single evaluating physician.

4. When Faced with “Dueling Docs,” Which One Is Given More Weight?

The NPD of Bergen v. Dept of Transportation, 2024 Cal. Wrk. Comp. P.D. LEXIS 133 illustrates the premise that if an AME’s reports constitute “substantial medical evidence,” then the AME’s evidence should be chosen as the “top doc,” unless good cause exists to dismiss it.

In Bergen, supra, applicant’s industrial injuries included the following two “red flags,” which is often a signal for a potential finding of permanently total disability (PTD). In these types of cases an AME is especially helpful for guidance:

a. Six lumbar spine surgeries (translation = “multiple failed back surgeries”); and

b. Daily use of narcotic medication required to function.

In Bergen, supra, the WCJ relied on the AME’s reports to find the applicant to be PTD, since parties typically select an AME because of that examiner’s expertise and neutrality.

The WCJ further explained,

“[W]orkers’ compensation law favors agreed medical examiners in resolving medical disputes fairly and expeditiously. (Green v. Workers' Comp. Appeals Bd. (2005) 127 Cal.App.4th 1426, 1444, 26 Cal. Rptr. 3d 527, fn. omitted.) Thus, an AME's opinion should be followed, unless there is good reason to find that opinion unpersuasive. (Power v. WCAB (1986) 179 Cal.App.3d 775, 782.)”

(See also Pantoja v. Jack in the Box, 2024 Cal. Work. Comp. P.D. LEXIS 304)

Practice Tip: This case also provides helpful hints on how to bullet proof an apportionment finding to non-industrial factors.

5. The AME = the Top Doc, But What If It’s the QME v. the PTP?

When the California Supreme Court speaks, people listen. This is especially true when there is a major paradigm shift in the law as occurred with the enactment of SB863 effective as of 1/1/2013. One of the tenets of this legislation was to set in play the single Panel QME system. Prior to this, parties were each allowed to secure their own evaluating physician. It was thought that with only one QME per body region, the legal process would be considerably expedited. However, after enactment of SB863, quite a controversy arose. What other type of medical evidence could a party obtain, in addition to the single Panel QME, to meet their burden of proof?

Ultimately, the question morphed into, “Whose report should be given more weight, the one from the Panel QME or the one from the primary treating physician (PTP)?”

The California Supreme Court in Valdez v. WCAB (2013) 57 Cal. 4th 1231, 78 Cal. Comp. Cases 1209, had the answer, sort of. If both reports constituted “substantial medical evidence,” then both reports should be admissible as evidence in a court of law pursuant to Labor Code § 4605 and Labor Code § 5703(a). Okay, that answers the question as to admissibility, but what about weight?

In the case of Fields v. The Regents of the Univ. of California, 2024 Cal. Wrk. Comp. P.D. LEXIS 269, medical evidence by both the PTP and the QME were admitted into evidence at trial. Who wins then? That would be the one with the more accurate “substantial medical evidence.” Although that’s often a difficult call to make.

In Fields, supra, the WCJ decided to follow the QME who determined that applicant’s industrial exposure to mold was not the cause of her condition of aspergillosis. He then issued a “take nothing.” The QME’s opinion was contrary to that of the applicant’s PTP. The PTP did find industrial causation, attributing it to applicant’s mold exposure at work.

When the case arrived at the Recon Unit, the WCAB referenced the case of Valdez supra, and concluded:

“As acknowledged by the Court in Valdez supra, sections 4060, 4064(d) and 5703 suggest an expansive rather than limiting approach by the Legislature regarding the admissibility of medical evidence. Accordingly, the PTP reports, which were properly admitted into evidence, are to be given the same weight as the QME's reporting.” (Emphasis added.)

However, for some reason, the WCAB in Fields, supra, didn’t rely on either the QME or the PTP in this case. Instead, they granted the appointment of a “regular physician” pursuant to LC §5701 and returned the matter to the trial level to develop the record on the evidence elicited from the “regular physician.” Go figure.

In the NPD of Breen v. State of California, 2023 Cal. Wrk. Comp. P.D. LEXIS 156, the WCAB affirmed the WCJ’s reliance on the PTP to award applicant a higher PD rating for an industrial impact injury to his left knee than the QME determined. The WCJ thoroughly discussed the rating process used by each of the two evaluating physicians. He then explained in depth how and why he decided to follow the rating of the PTP, over the QME. This is exactly the kind of thorough discussion needed to determine if the report constitutes “substantial medical evidence” upon which a WCJ may rely for an accurate PD determination.

6. When Does a “Regular Physician” per Labor Code § 5701 Know Best?

It is the action of the WCAB in Fields, supra, that brings us to our concluding chapter in this saga of the “dueling docs.” When and why does the Labor Code § 5701 “regular” doctor “Know Best?” The appointment in Fields, supra, was quite sudden and unexpected, with no real explanation as to the basis for this decision.

Perhaps some guidance can be found in the NPD of Gomez v. Sweetwater Union High School Dist., 2024 Cal. Wrk. Comp. P.D. LEXIS 130. After the trial, while examining the evidence, the WCJ in Gomez supra, found that neither the evidence authored by the QME in orthopedics nor the reports by the PTP specializing in pain management constituted “substantial medical evidence.” The WCJ had no choice but to vacate his submission order and to order the parties to develop the record using a Labor Code § 5703 “regular physician.” Dr. Thompson, a pain management specialist, was then appointed to determine applicant’s WPI.

There’s no explanation as to why the WCJ felt this appointment was necessary. However, if one reads the description of the reports summarized, the reason for the regular physician’s appointment becomes evident.

In Dr. Thompson’s first report, he placed applicant’s injury within Class III of Table 13-15 (20%–39% WPI). This was due to his belief that applicant required a cane to ambulate.  Subsequently, he was provided with hard core evidence that applicant could, indeed, walk without assistance. He then issued a second report wherein he placed applicant’s injury in Class II of Table 13-15 (10%–19%) Inexplicably, the WCJ rated applicant’s injury using Dr. Thompson’s first report based on that inaccurate history.

After defendant filed a Petition for Reconsideration, the WCAB issued an opinion which summarized the definition of “substantial medical evidence.” They firmly explained that Dr. Thompson’s first report didn’t rise to this standard:

“Here, Dr. Thompson's initial impairment rating was based on the understanding that applicant used the cane to walk almost all the time. However, Dr. Thompson's subsequent report…clarified that applicant was sometimes able to walk without a cane. Therefore, Dr. Thompson's initial impairment rating no longer constituted substantial medical evidence because it was based on facts that were no longer germane, and Dr. Thompson adequately explained why Class 2 of Table 13-15 better reflected applicant's permanent impairment. The issue of applicant's permanent impairment was a matter of expert scientific knowledge, and the WCJ erred in rejecting the expert evidence.”

7. Does Employee's Self-Procured Medical Report Carry Any Weight?

Any article on “substantial medical evidence” would be remiss if there was no discussion as to medical reports admissible under Labor Code § 4605. This section allows an employee, at their own expense, to obtain a consulting or any attending physician’s report related to their case.

However, any such report “shall not be the sole basis of an award of compensation.” A QME or PTP who is already an authorized evaluating physician in the case is required to “address any medical report procured by this section and shall indicate whether he or she agrees or disagrees with the findings or opinions stated in that report and shall identify the bases for this opinion.”

Thus, the self-procured report may be considered by a WCJ when formulating his or her legal decision. However, it cannot be the sole basis for that opinion.

8. “Substantial Medical Evidence” Checklist

It would be advisable for parties to create a “substantial medical evidence” checklist comprised of the requirements of Labor Code §4628 and Regulation 8 Cal. Code Reg. § 10606.

In addition, the WCAB’s roadmap on this issue, Escobedo v. Marshalls (2007) 70 Cal. Comp. Cases 604 (Appeals Board en banc) should be reviewed at least once a year as a reminder of the roles each participant plays in the process. Especially important in this case is the admonition to evaluators to base ALL conclusions on “reasonable medical probability.”

And there you have it, a concise explanation of what constitutes “substantial medical evidence” and where to find it. And perhaps more important, when it is necessary to meet your burden of proof, so that when your case is teetering on the edge of prevailing, the medical evidence will push your client’s case to victory.

Reminder: Board panel decisions are not binding precedent.

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