One Number Decides What Your Case Is Worth
At some point in a serious California comp claim, your injury gets converted into a percentage. Twelve percent. Thirty-one percent. Whatever the number is, it will determine how many weeks of permanent disability you’re paid, and it will anchor every settlement conversation that follows.
Most injured workers see that number for the first time on a piece of paper, with no idea how it was constructed or that it could have been constructed differently. Understanding how it’s built is the difference between accepting a rating and evaluating one.
It Starts at Permanent and Stationary
Nothing gets rated until you’re permanent and stationary — meaning your condition has stabilized and isn’t expected to materially improve with further treatment. In more current usage you’ll also see “maximum medical improvement.”
Two things about that milestone are worth knowing.
First, it is a medical opinion, not a fact, and doctors can reach it too early. A treating physician who declares you permanent and stationary while you’re still actively improving locks in a rating that understates where you would have ended up.
Second, it changes your benefits. Temporary disability generally ends at permanent and stationary, and the case moves into its permanent phase. If you’re surprised to be declared stable, that’s worth raising immediately rather than after the report is final. Our article on temporary versus permanent disability covers the distinction in more detail.
How the Rating Gets Built
California builds a permanent disability rating in layers. Each one can be argued.
1. Whole person impairment
The evaluating physician assigns an impairment rating under the AMA Guides to the Evaluation of Permanent Impairment, Fifth Edition — the standard California uses. This is a clinical measurement: range of motion, strength, neurological findings, diagnosis-based criteria depending on the body part.
This is the foundation, and errors here propagate through everything downstream. An incomplete examination, a body part left unaddressed, or a measurement taken on a good day produces an impairment number that is wrong before any adjustment is applied.
2. Statutory modifier
The impairment is adjusted by a statutory factor. For injuries on or after January 1, 2013, California applies a flat modifier in place of the older future-earning-capacity adjustments used for earlier dates of injury.
3. Occupational adjustment
Your occupational group then adjusts the figure. The same shoulder impairment means something very different for a framing carpenter than for a dispatcher, and the schedule accounts for that.
This step is more contestable than it looks. Occupational group assignment depends on what you actually did, not on your job title. “Maintenance worker” covers an enormous range. If your group number was assigned from a title rather than a real description of your duties — the weights, the climbing, the tools, the conditions — the adjustment can be materially wrong.
4. Age adjustment
Your age at the time of injury adjusts the rating, on the reasoning that the same impairment affects remaining working life differently at 28 than at 58.
5. Apportionment
Finally, apportionment divides the disability between industrial and non-industrial causes. Only the work-related share is compensable.
This is where the largest reductions happen, and where cases are most often quietly lost. An evaluator who attributes half your spinal disability to degenerative change has cut your award in half in a single sentence — a sentence that may or may not be well supported.
What the Percentage Actually Buys
The final percentage converts to a number of weeks of permanent disability payments under the statutory schedule, paid at a weekly permanent disability rate.
The relationship is not linear — higher percentages yield disproportionately more weeks, so a few points of rating can be worth considerably more than they appear. That’s precisely why arguing about what looks like a small difference in impairment is often worth doing.
At 100%, the disability is permanent total, which carries lifetime payments.
Where Ratings Go Wrong
In practice, the recurring problems are these:
- An incomplete evaluation. Body parts you complained about that never made it into the report, because they weren’t in the referral or you didn’t raise them clearly.
- A thin job description. The occupational adjustment built on a title rather than actual duties.
- Unchallenged apportionment. A conclusory statement that half your disability is degenerative, accepted because nobody pushed on it.
- Premature permanent and stationary status. Rated while still improving.
- Psychiatric or sleep components never addressed. Where legitimately present and properly supported, these can add to a rating — and they are routinely omitted.
- Nobody explaining the report to the worker. The rating arrives, it’s incomprehensible, and it goes unquestioned because it looks official.
Every one of these is addressable — before the report becomes the settled record. Afterward, it’s much harder.
Challenging a Rating
A rating you believe is wrong isn’t necessarily final. Depending on the posture of your case, the avenues include supplemental reports from the evaluating physician addressing what was missed, a deposition of the evaluator, cross-examination, and in some circumstances a further evaluation.
All of these are time-limited and procedurally technical, which is the real argument for getting advice as soon as a report you disagree with arrives — not months later when the case is being settled.
Frequently Asked Questions
How is permanent disability calculated?
A physician assigns whole person impairment under the AMA Guides, Fifth Edition. That figure is adjusted by a statutory modifier, your occupational group, and your age, then reduced by any apportionment.
Does my percentage mean I lost that much of my body?
No. It’s a scheduled measure that converts to weeks of payments, not a statement about your body or how disabled you feel.
Why did my rating drop because of apportionment?
Because only the work-related share of your disability is compensable. Whether the apportionment opinion is properly supported is a separate — and contestable — question.
Can I be rated for more than one body part?
Yes, multiple impairments can be combined under the schedule. Making sure every affected body part is actually evaluated is one of the most valuable things you can do before the exam.
What if I’m rated but still can’t work?
A rating short of 100% doesn’t mean you’re employable in practice. Depending on your circumstances, a job displacement voucher, vocational evidence, or Social Security Disability may be relevant.
Have the Report Reviewed Before It Becomes Final
A permanent disability rating is built from a medical report, a job description, and an apportionment opinion. Each of those can be incomplete, and each is far easier to fix before it hardens into the record everyone settles from.
Kim LaValley and Kyle Adamson have reviewed permanent disability ratings for injured workers in Nevada County, Placer County, and throughout the Sierra foothills for decades. If a report or a rating has landed and the number doesn’t match your reality, call 530-362-7188. Reviewing it costs nothing.
Read more about permanent and stationary status and California workers’ compensation claims.
This article is general information about California workers’ compensation law and is not legal advice. Permanent disability ratings depend on your specific medical findings, date of injury, occupation, and age. For advice about your rating, speak with a workers’ compensation attorney. Authoritative source material: California Division of Workers’ Compensation; the California Permanent Disability Rating Schedule.
