The document examines the concordance between the costs of allied health professional activity and diagnosis-related group based reimbursement using hospital administrative data from New Zealand. It analyzes the top diagnosis-related groups that receive allied health input to determine if allied health costs and actual costs both increase over length of stay. The results show that allied health staff costs do not increase over length of stay as much as actual costs, and there is a significant interaction between allied health costs and actual costs in influencing length of stay.