CWCI’s analysis of cumulative trauma claims in the California workers’ compensation system uses data from 1.4 million claims with claims administrator notification dates of 2010 through 2022 to track the growth in all CT claims and litigated CT claims. The report explores key variables associated with CT claims, analyzes litigation rates and the mix of stand-alone vs. group claims, and uses regression analyses to estimate the impact of variables such as region, tenure, industry, claimant age, and average weekly wage on CT rates for litigated claims. Research Note, $21.