A retrospective chart review of 257 patients who presented between January to March 1998, was conducted to identify the frequency of workers' compensation claim denial among patients who reported to Straub Clinic and Hospital. Results showed that 12.8% of claims were either "denied" or temporarily "denied pending investigation". Analysis of all the claims found that only 2% resulted in delayed medical care. Further analysis of the denied claims revealed the vast majority of claims (78.8%) were denied because the medical provider and the patient had incorrect workers' compensation carrier information. Other independent variables studied (size of the employer, category of employer, injury type, status of case, length of case and number of visits) did not predict either denial of the claim or treatment delay. This study suggests that the efficiency of our State's Workers' Compensation system would be greatly improved by developing a system to provide medical care providers with accurate insurance information.