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• Marjory Harris





SB 899 was hailed as reform legislation which would, among other things, prevent employers from having to pay for permanent disability that was not caused by the particular employment claimed as the basis for the injury. Revised Labor Code §4663 required that apportionment "shall be based on causation" and required a physician to "make an apportionment determination by finding what approximate percentage of the permanent disability was caused by the direct result of injury arising out of and occurring in the course of employment and what approximate percentage of the permanent disability was caused by other factors both before and subsequent to the industrial injury, including prior industrial injuries."

"Science" is not a term used in this legislation. While the words "scientific" or "scientifically" appear in SB 899, it is only in relation to medical treatment guidelines and utilization review. Labor Code §4604.5(b) requires that the recommended guidelines or the medical treatment utilization schedule (MTUS) "shall reflect practices that are evidence and scientifically based, nationally recognized, and peer-reviewed." No such requirement was inserted in the revised statute on apportionment.

The Escobedo decision [Escobedo v. Marshalls (2005) 70 Cal. Comp. Cases 604 (Appeals Board en banc opinion), pet. for rev. den. sub nom. Escobedo v. W.C.A.B. (2005) 70 Cal. Comp. Cases 1506 (writ denied)] provided guidelines for physicians and workers' compensation administrative law judges for determining whether the apportionment amounted to "substantial evidence."

In the first article in this series, entitled "Apportionment: Science or Science Fiction?" we decried the illogical and confused apportionment opinions of physicians. The passage of time has not improved the clarity or cogency of these opinions, whether medical or judicial. Here are some examples:

After apportioning 30% of the permanent disability in a knee case to obesity and smoking, the AME testified in deposition:

Q. And what is the basis of your attributing 30 percent to nonindustrial factors?

A. Well, that's probably the toughest one, and there is some good high-quality studies that show that things like smoking and obesity have a significant effect on multiple joints, and in this case, knee, certainly. Again, those studies don't give you the information to say 30 percent or 20 percent or 60 percent. So you have to rely on expert medical opinion again.

Q. Okay. And is her aging process contributing as a nonindustrial factor to her overall disability?

A. It is, but I would include that in the obesity part.

Q. How is her obesity contributing to her overall disability?

A. How is a tough question. I didn't design this equipment. I just service it. And many times over -- medical doctors or scientists have sort of thought logically that just the pressure on the knee may be the thing that's doing it in this case. It turns out that the human body is much more complex than that, and we're fooled many times. So I don't know for sure how. I do know there's a correlation, a connection. Some people speculate that the fat cells themselves excrete hormones, they can tear up joints, because obese people many times not only have problems with their knees and hips where they would bear the weight but also their fingers where you wouldn't expect it.

Q. And how is smoking contributing to her overall disability?

A. No idea, but it does.

Q. Okay. And what do you base that on?

A. Scientific studies that show an increase in joint problems in people who smoke.

Q. Okay. Are there epidemiological studies in this regard?

A. That's right.

Q. Now, if she has problems in her right knee as a result of smoking and obesity, wouldn't she have similar problems in the left knee?

A. Well, she may have problems in the left knee, as we've talked about. I really wasn't focusing on the left knee. She doesn't have symptoms in the left knee.

Q. But you're not sure for a fact that she does?

A. She doesn't have symptoms. That's what I'm sure of. That doesn't mean she doesn't have arthritis in there at a level that is subclinical, let's call it.

Labor Code §4663,
in relevant part

(a) Apportionment of
permanent disability shall
be based on causation.
(b) Any physician who prepares a report addressing the issue of permanent disability due to a claimed industrial injury shall in that report address the issue of causation of the permanent disability.
(c) In order for a physician's
report to be considered
complete on the issue of
permanent disability, it must
include an apportionment
determination. A physician shall make an apportionment
determination by finding what
approximate percentage of
the permanent disability was
caused by the direct result
of injury arising out of and occurring in the course of
employment and what approximate percentage of
the permanent disability was caused by other factors both before and subsequent to the industrial injury, including prior industrial injuries.

For the entire statute,
click here

Apportioning to Causation of
Permanent Disability

I have read numerous forensic evaluations since the dust settled in April 2004 and have attended many depositions since then. I am convinced that most doctors, many lawyers and almost all claims adjusters think that “substantial evidence” is established when the doctor utters magic words like “reasonable medical probability” and “expert medical opinion.” That somehow these magic words obviate the need to explain the how and the why. Escobedo is still the law, and we must insist on compliance.

Try some IPECAC:


I – Issue (Is there any percentage of permanent disability attributable to factors other than the industrial injury?) If yes, go to the next step.

P – Premise (what is the physician's premise for apportionment to non-industrial factors?)(e.g., obesity causes knee problems – epidemiologic risk factor)

E – Erudition, or knowledge acquired through study and reading, and Evidence. This is a requirement of the new paradigm of "evidence-based medicine" (EBM). Anything less is anecdotal and likely the "ipse dixit" logical fallacy

C – Causal relationship and the weighing of counter evidence: Even if there is EBM to support the premise, is there evidence that does not support the premise? In other words, does the EBM show cause and effect or simply correlation? If not dispositive of the issue, proceed to the next step (do studies show that all obese people have knee problems? Or that if bones are malaligned, obesity then causes problems?)

A – Application and Analysis: how does this relate to the facts of this case and this injured worker? Connect all the dots! ("This IW has obesity and malaligned bones")

C – Conclusion re: causation. Is the conclusion logically derived from the premise, the erudition and evidence, the weighing of causes and counter evidence, and the facts of the instant case? If not, examine further for logical fallacies, contrary studies, and legal attacks based on case law, other laws such as FEHA, concepts of fairness, Labor Code §3202, etc. and the like.

IPECAC for analyzing apportionment:
Erudition & Evidence
Causal Relationship &
Counter Argument
Application & Analysis
Conclusion re: Causation

Click here to download a chart to take with you to depositions. It summarizes IPECAC and includes questions to support or refute apportionment.

Key Questions to Eliminate or Limit Apportionment

Apportioning to pre-existing pathology
Q. Is there any indication of disability before the industrial injury in question?

Q. Absent the industrial injury in question can you say, without speculating, whether the injured worker would have a disability today?

Q. What is the scientific basis for apportioning to pathology in the absence of a history of disability?

Q. Is there any way to predict without speculating when the silent pathology would have caused symptoms?

Distinguish pathology as
the cause of injury from
pathology as the cause
of current disability

Apportioning to genetics, degeneration,
and lifestyle

Q. Please provide any evidence-based studies which show that such lifestyle and genetic factors actually caused the disability now experienced by this particular injured worker?

Q. Doctor, are you saying that if the applicant stayed at home for the past 33 years, doing light housekeeping, instead of working those 33 years in heavy labor, he would still have the same degree of degeneration he has today?"

Q. What medical proof is there for some "natural degenerative process" that results in spinal disability?

Q. If this is some natural process, why is it only a percentage of people have it?"

Q. You apportioned to time spent sleeping. Isn’t sleeping a restorative process?

Q. You have referred to epidemiologic studies as showing that X can cause Y, but can you say with reasonable medical probability in this case that X caused Y?

Apportioning to Race, Age, Sex, etc.
Q. Doctor, can you separate the aging process from the [age-related condition]?

Q. Do all people of this [race, sex, age] have this [pathological condition]? If all do not, then how can you say in this particular case that the injured worker’s disability is partially due to his/her [race, sex, age]?

Government Code §11135(a)
No person in the State of California shall, on the basis of race, national origin, ethnic group identification, religion, age, sex, color, or disability, be unlawfully denied full and equal access to the benefits of, or be unlawfully subjected to discrimination under, any program or activity that is conducted, operated, or administered by the state or by any state agency, is funded directly by the state, or receives any financial assistance from the state.

On August 20, 2008, SB 1115 “to bar the consideration of race, national origin, gender, sex, genetic predisposition, and certain other factors in the determination of an apportionment of the causes of an industrial disability,” passed the State Assembly and went to the Governor.

Apportioning to Age vs. Age-Related
Degenerative Conditions
Some more magic dust, please! While the Vaira case [Vaira v. WCAB (2007) 35 CWCR 307 (CA 3d non pub)] said that apportionment to age violates the anti-discrimination provisions of the Government Code, it allowed apportionment to a prior age-related condition lit up by the current injury. To avoid this illogical result, focus on the underlying fact that the condition is caused by age or degeneration resulting from the aging process or premature aging due to the type of work the worker did.

Q. Doctor, can you separate the aging process from the [age-related condition]?

If the answer is “yes,” probe into the methodology, scientific studies and the like.

Vaira v. WCAB (2007) 35 CWCR 307 (CA 3d non pub)

Apportioning to CT and Specific Injuries
The third way to carve up permanent disability is to take a work injury where there was no previous or subsequent disability, and no apportionment to non-industrial “other factors,” and to find that some of the PD is due to the specific event and the remainder due to cumulative trauma while working for the same employer. This is the situation in the Benson case which has been appealed to the First District Court of Appeal.

Q. Did the second injury prevent the first from healing properly?

Q. Did the first injury render the injured body part sufficiently weak or sensitive so that it contributed to the damage caused by the second injury?

Q. Would it be speculative to separate the two injuries due to the proximity in time when the injuries occurred?

Q. Please explain the medical basis to separate the effects of the two injuries causing the overall disability?

Q. Is the disability or impairment caused by one injury so insignificant that all residual disability is attributable to the other injury?

Q. Is there a synergistic effect between the two (or more) injuries which does not allow the permanent disability from one to be separated from the permanent disability from the others?

Q. Is the overall disability greater than simply the sum of the injuries, such that each part cannot be reasonably evaluated separately?

Benson v. The Permanente Med’l Group et. al. (2007) 72 C.C.C. 1260. In an en banc decision, the Workers’ Compensation Appeals Board abrogated the Supreme Court’s 1977 decision in Wilkinson v. WCAB (1977) 19 Cal. 3d 491, 42 C.C.C. 406. The 1st DCA Granted a Writ of Review on 6/26/08.
Maybe it’s a compensable consequence injury
Q. Without the specific injury, would there have been a cumulative trauma? Put another way, had IW not had the specific injury of [DOI] and been examined by you on [date of exam], would you have been able to diagnose a cumulative trauma?

Q. How and why does any specific condition found in this case cause the permanent disability you observed on [date of exam]?

Q. Without the cumulative trauma, would there have been a specific injury? Put another way, had IW not had the cumulative trauma of [DOI] and been examined by you on [date of exam], would you have been able to diagnose a specific injury?

Q. How and why does any cumulative trauma found in this case cause the permanent disability you observed on [date of exam]?

Labor Code §3208.1
An injury may be either: (a) "specific," occurring as the result of one incident or exposure which causes disability or need for medical treatment; or (b) "cumulative," occurring as repetitive mentally or physically traumatic activities extending over a period of time, the combined effect of which causes any disability or need for medical treatment. The date of a cumulative injury shall be the date determined under
§ 5412.
Carving Up PD: Part II
By Marjory Harris

Fourth in a series of editorials on “Workers’
Compensation Disabled: What Went Wrong on
the Road to Reform?” we explore recent trends
in apportionment of permanent disability and provide some suggestions on
how to attack attempts to carve up PD. In the last issue, we discussed three
major methods of carving up permanent disability. In a previous article, we
discussed the science and the fiction behind Labor Code §4663.
> The Doctor's Office: Chiropractic
> Multiple Impairments & DFEC
> Defense Perspective: EAMS
> Computer Corner:
Getting on Top of ToDos
> Carving up PD: Part II