Many workers' compensation (WC) claims result in no payment from the WC system, but do lead to increased costs for employee group insurance plans, reports a study in the December Journal of Occupational and Environmental Medicine, official publication of the American College of Occupational and Environmental Medicine (ACOEM).

Nationwide, so-called zero-cost WC claims could cost group health insurance plans more than $200 million per year, according to the study by Abay Asfaw, PhD, and colleagues of the National Institute for Occupational Safety and Health.

The researchers analyzed data on more than 12,000 injured workers who filed for WC insurance from 2002 through 2005. Sixteen percent of the claims were "zero-cost" claims — that is, they resulted in no WC payments.

Use of and payments from the employees' group health insurance increased after WC claims. That was so for zero-cost claims as well as claims resulting in payments.

But the zero-cost claims were associated with significantly greater increases in costs to group health insurance, after adjustment for other factors. The increase was largest for outpatient care, with an estimated increase of approximately $400 per claim.

"Our national estimated showed that zero-cost WC claims added $212 million in medical bills to group health insurance per year," the researchers write. Because their data may miss some occupational injuries, they suspect the true economic impact is even higher.

The study adds to previous evidence suggesting that non-WC insurance — including not only employee health plans but also public insurance — cover at least part of the costs of work-related injury and illnesses. "If WC provides inadequate coverage…workers will seek treatment using other insurance," Dr Asfaw and coauthors conclude. "Our key finding is that zero-cost WC medical claims have repercussions for other insurance systems and society, and their economic implications are substantial."