Variation in specialist fees: evidence from New Zealand insurance claims

To examine the parity between specialties in reimbursements for surgical procedures in a private, fee-for-service setting and to ascertain whether differences exist after accounting for factors suggested by a Resource-Based Relative Value Scale (RBRVS).

A routinely updated database covering several private insurers (n = 8294 procedures from 1997 to 2002) was used to examine differences in overall and hourly reimbursement. Multiple regression analysis was used to control for factors that might be responsible for differences in payment (location, year, sex of patient and the associated anaesthetist fee). The resulting regression residuals were compared between specialties.

Large differences between specialties in reimbursements were found in the overall amount paid. For most specialties, these differences were explained by factors such as time for procedure, location, complexity of procedure and sex of patients. However, hourly reimbursements for ophthalmologists were substantially higher (more than 50% above general surgery overall and 72% higher on an hourly basis). Some other smaller differences in overall and hourly reimbursement were also found.

These results indicate that specialist fees vary significantly but many of the differences are explainable by factors incorporated into the RBRVS. However, significant variation remains for some specialties, most notably ophthalmology. Explanations for the results are discussed, including the possibility that political factors may influence the setting of specialist fees. This raises questions concerning the fairness of reimbursements and resulting solidarity within the medical profession.