Delays in reporting work-related injuries can cause workers compensation claim costs to increase by up to 51%, according to the National Council on Compensation Insurance Inc.Claim costs for occupational injuries reported between one to two weeks after the date of an accident represented the lowest median cost at $13,210 per claim, Boca Raton, Florida-based NCCI said in a report released Tuesday. Injuries reported between one day and one week after an accident resulted in the second lowest average cost per claim at $13,844.