How a rating is computed.

The physician's WPI from the AME/QME report is the input. Values reported in a native AMA scale (UE, LE, hand, foot, digit) are converted to WPI first.

Up to 3% may be added for pain that exceeds the chapter rating — capped at 3% across the whole case, then rounded to a whole percent.

For injuries on or after Jan 1 2013, the adjusted rating is WPI × 1.4, rounded (SB 863). For injuries from 2005–2012, the original FEC adjustment applies instead: each impairment carries an FEC rank 1–8, and the rating string shows the rank, e.g. [5]45.

The occupational group (from the job title) and the impairment number select a variant letter; the variant maps the adjusted rating to an occupationally-adjusted rating.

The worker’s age at injury places the rating in a 5-year bucket that adjusts it up or down.

Per-impairment industrial causation is applied (§4663). Multiple impairments are combined via the Combined Values Chart — never simple addition — largest first.

Dates of injury on or after January 1, 2005 — the FEC era (2005–2012, rank-based adjustment) and the SB 863 era (2013+, flat ×1.4). Pre-2005 injuries rate under the 1997 schedule, which is out of scope. Note for 2005–2012: the §4658(d) ±15% return-to-work rate adjustment is employer-dependent and not applied.

No. RateString rates strict AMA Guides values. Alternate (Almaraz/Guzman) ratings and Kite arguments are left to the practitioner — you can enter an AME-supplied number via the override.

The PD/TD weekly-rate caps (Lab. Code §4453) are versioned by year of injury, so a rating never runs on a stale table. The §4658 PD-weeks schedule itself is identical for every date of injury from 2005 on — the calculator applies it verbatim from the statute.

No. RateString produces estimates for informational use only. Always verify a rating against the DEU before relying on it.