What is the DEU in California workers’ comp?

The Disability Evaluation Unit is the arm of the Division of Workers’ Compensation whose raters convert medical reports into permanent-disability ratings under the rating schedule. It issues summary rating determinations on qualifying medical reports and consultative ratings in other settings.

What is a summary rating determination?

A document from the DEU that translates a QME or treating physician’s report into a formal PD percentage. Its core is one rating string per rated impairment plus the combined final percentage; the money then follows from the statutory tables for the date of injury.

Is a DEU rating final?

No — it is a rating of a report, not a judgment. It carries real weight (especially in unrepresented cases), but it can be challenged: the underlying medical report can be disputed, apportionment can be litigated, and rating errors can be corrected. Deadlines for objecting are short, so act promptly and verify the current rules.

Why does my calculation differ from the DEU’s?

Almost always one of four inputs: a different occupational group, a pain add-on the rater did or didn’t include, apportionment applied differently, or the wrong era/date-of-injury assumptions. Compare the strings segment by segment and the divergence point becomes obvious.

What a DEU Rating Is — and How to Read the Determination

What California’s Disability Evaluation Unit does, what a summary rating determination contains, and how to read — and check — the rating string at the heart of it, line by line.

Sooner or later every California comp file produces a rating from the Disability Evaluation Unit — the DWC’s own raters. It arrives as a dense page of numbers, and buried in it is everything that matters: the rating string for each impairment, the combined percentage, and the basis for the money. This guide is about reading that document fluently — and checking it.

What the DEU actually does

The DEU doesn’t examine anyone. It rates reports: a rater takes the physician’s whole-person impairment findings and runs them through the 2005 rating schedule — the same pipeline described in How PD is calculated. For qualifying unrepresented cases that output is a summary rating determination; in represented and litigated settings the DEU also issues consultative ratings on request. Either way, the math is the schedule’s math — which means you can reproduce it, step for step. And the unit’s workload is measurably shrinking: CHSWC’s 2025 annual report puts DEU written ratings near 60,000 a year through 2017, then down 32% by 2024 — consultative ratings (the attorney-requested kind) average 71% of what remains, and formal ratings have fallen more than 5.5-fold. Fewer official ratings in the system is one more reason a string you can check yourself matters.

The heart of the document: the rating string

Each rated impairment appears as one line. Here is a real one, computed by our engine for a 2023 low-back injury (occupational group 230):

100% (15.03.01.00 - 8 - [1.4]11 - 230E - 10 - 11) = 11% PD

Reading left to right: 100% is the industrial share (no apportionment); 15.03.01.00 is the impairment number (lumbar spine, DRE method); 8 is the physician’s WPI; [1.4]11 is the SB 863 earning-capacity adjustment (8 × 1.4, rounded); 230E is the occupational group and variant; 10 is the occupationally-adjusted rating; 11 is the age-adjusted rating; and 11% PD is that impairment’s final. The full segment-by-segment tour lives in How to read a rating string.

Apportionment shows up inside the string

When the physician apportions, the leading percentage changes and the final drops. Same case, shoulder impairment, 80% industrial:

80% (16.02.02.00 - 13 - [1.4]18 - 230G - 20 - 23) = 18% PD

The pipeline inside the parentheses runs exactly as before and reaches 23 — then the 80% is applied to produce 18. If a determination’s apportionment surprises you, this is the first place to look: the un-apportioned value is sitting right there before the close-paren. (Why apportionment costs more dollars than rating points: How apportionment works.)

From strings to one number

Multiple impairments never add — they combine on the Combined Values Chart, largest first. Our example case has finals of 18, 11, and 7:

Combining · demo case

18 C 11 = 27 → 27 C 7 = 32% PD
At 32%, a 2023 date of injury pays 145.00 weeks — $42,050 at the maximum PD weekly rate.

Every intermediate step is on the chart (the CVC, explained), and the weeks-and-dollars conversion comes from the statutory tables for the date of injury — see the rate tables by year.

How to check a determination (or an opponent’s rating)

Because the string exposes every intermediate value, checking a rating is mechanical. Enter the same date of injury, age, occupation, and each impairment’s WPI into the calculator — it produces the same style of string, live. When your number and theirs diverge, compare segment by segment; in practice the culprit is nearly always one of these:

The occupational group (a different job title mapping — check the group index); a pain add-on (up to +3 WPI, included or not); apportionment (the leading percentage); or the era (2005–2012 FEC ranks versus the 2013+ flat 1.4 — visible at a glance, because FEC-era strings carry a bracketed rank like [5] instead of [1.4]).

If you disagree with it

A determination is a rating of a report — not a final adjudication. Depending on posture, the medical report itself can be supplemented or disputed, the rating can be challenged for schedule errors, and apportionment is often the real battleground. The one universal rule: objection windows are short. If a summary rating just arrived and something looks wrong, treat the clock as already running and verify the current procedural deadlines immediately — or get counsel who will.

RateString produces estimates for informational use; it doesn’t give legal advice, and nothing here substitutes for the current regulations or a lawyer’s judgment on your facts.