After nearly a decade of steady declines, the number of inpatient hospitalizations in California workers’ compensation has leveled off, falling by less than 1% in both 2023 and 2024, according to a new California Workers’ Compensation Institute (CWCI) review of state data. At the same time, inpatient spinal surgeries, once a major cost driver in the system, are again trending down, and are now at roughly one-third of their 2013 level.
The findings come from a CWCI analysis of hospital discharge data compiled by the California Department of Health Care Access and Information (HCAI). CWCI incorporates the data, which includes details on 2013-2024 discharges, into its Inpatient Hospitalization Data Application, an online tool that allows the Institute to track and compare various aspects of inpatient utilization, including the number of stays, diagnoses, types of treatment, lengths of stay, and average charges across workers’ compensation, Medicare, Medi-Cal, and private insurance.
Workers’ compensation represents a tiny share of inpatient care in California. In 2024 there were 10,332 workers’ comp inpatient discharges out of 2.7 million statewide (excluding childbirth-related discharges which are not covered by workers’ compensation). Across all four systems, inpatient volume rose 10% between 2013 and 2024, though trends varied widely among the payer systems. Much of the increase was tied to Medi-Cal’s expansion following the Affordable Care Act and recent eligibility changes. Excluding the childbirth stays, over that 12-year span, Medi-Cal hospitalizations increased 55.9% while Medicare hospitalizations rose 9.3%. In contrast, privately insured inpatient stays declined 21.3% while workers’ compensation inpatient stays fell nearly 50%, reducing its share of statewide hospitalizations from 0.82% in 2013 to 0.38% in 2024.
The long-term decline in workers’ compensation inpatient stays reflects multiple factors, including changes in claim volume, the adoption of Utilization Review and Independent Medical Review, medical advances, and a shift toward outpatient care. Policy changes also played a role. For example, reforms that eliminated duplicate payments for spinal surgery hardware and expanded evidence-based guidelines for spinal fusions contributed to a steep drop in inpatient spinal surgeries. These procedures, which averaged $237,554 in hospital charges in 2024, declined by 56.9% from 4,357 cases in 2013 to 1,877 cases in 2020, and after a modest uptick during the pandemic recovery in 2021 and 2022, they resumed their decline, falling to 1,429 cases in 2024, down 67.2% from 2013, and a new post-reform low. Notably, CWCI’s review of the HCAI data found that since 2013, the overall mix of inpatient diagnoses has remained relatively stable. Musculoskeletal and connective tissue diseases and disorders continue to account for most workers’ comp hospitalizations, though that share has declined modestly in recent years. Nervous system disorders rank second, followed by injuries, poisonings, and toxic effects of drugs. Respiratory conditions, which spiked during the pandemic, have since returned to pre-pandemic levels.
At the same time, the nature of inpatient care is changing. As more procedures move to outpatient settings, the remaining inpatient cases are often more severe, involving more intensive care and longer stays. This is reflected in a 33.4% increase in the average length of stay, from 4.55 days in 2013 to 6.07 days in 2024. The longer stays, in turn, contributed to rising charges, as the average hospital charge per stay rose 86.2% from $105,408 in 2013 to $196,227 in 2024.
CWCI will continue to monitor these trends and update its Inpatient Hospital Utilization Data Application as new data become available.
View source version on businesswire.com: https://www.businesswire.com/news/home/20260507383590/en/
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