The California Workers’ Compensation Institute (CWCI) published a new study analyzing a sample of 1.4 million California claims from 2010-2022 to examine changes in cumulative trauma (CT) claims and litigated claims in the California workers’ comp system.
The study found that CT claims increased from 29.4% of all litigated claims to 37.5% of all litigated claims over the 13-year study period. Over that same period, CT claims’ share of all litigated claims was fairly stable in Northern California and the Central Valley, but increased in 2022, while in Southern California CT claims’ share of the litigated claims increased steadily throughout the period.
The following increases were seen across different regions from 2010-2022:
- The Inland Empire/Orange County saw CT claims jump from 30.2% of litigated claims to 40.6% of litigated claims
- Los Angeles County saw CT claims increase from 38.6% of litigated claims to 48.7% of litigated claims
- San Diego saw CT claims increase from 25.0% of litigated claims to 33.4% of litigated claims
Other than regional factors, differences in tenure had the strongest impact on differential CT rates. Employees with less than a year of tenure at the time of injury had a much lower CT rate (26.0%) than more tenured workers. CT rates increased incrementally as tenure increased, climbing as high as 49.0% among workers with more than 10 years on the job.
A review of the CT rates across nine major industry sectors showed that CT claims were most prevalent in the manufacturing sector, where they accounted for nearly half (48.8%) of the litigated claims, which was almost twice the proportion noted in the construction sector.
The food service sector had the second highest CT rate, with 46.9% of the claims in this sector involving CT injuries, while the agriculture sector had the lowest CT rate (24.2%). Regression results showed that while the type of industry influences CT rates, for most sectors other factors such as region and job tenure play a comparable role.
Workers under the age of 30 had a somewhat lower CT rate (28.3%) than workers who are over 30, whose CT rates ranged from 35.1% to 38.8%, though more than a third of all CT claims in the study involved injured workers who were under 40. Regression analysis showed that age is not a strong predictor of CT rates compared to other factors.
