Audit of surgeon billing in workers compensation-insured elective spinal surgery in New South Wales, Australia from 2010 to 2018.

BACKGROUND: Medical billing practices have received increasing scrutiny in Australia and worldwide. In 2015, the Australian Government initiated a comprehensive review of the Medicare Benefits Schedule (MBS), including spinal surgery. This study provides a snapshot of five spinal surgeon billing patterns and associated costs in the workers compensation system in New South Wales prior to these changes. METHODS: This retrospective cohort study used workers compensation billing data from the State Insurance Regulatory Authority to capture elective spinal surgeries in New South Wales from 2010 to 2018. The main outcome measures were: proportion of items billed within recommended limits (up to 150% of the listed Australian Medical Association (AMA) fee); surgical billing patterns including repeat billing of items during a single episode of surgery; use of paediatric or scoliosis items; use of surgical items from outside the spinal surgery schedule; co-billing of items not permitted as per the AMA Fees List item descriptions and associated costs. RESULTS: There were 12 622 spinal surgeries in 9520 patients. While only 2.2% of items were billed above the recommended limits, 38% of surgeries included at least one of the five billing patterns. The average cost increase was AU$4700 per surgery, 47% greater than surgeries which did not include the specified billing patterns, for a total additional cost of AU$22.9 M over the 9-year study period. CONCLUSION: Five spinal surgery billing patterns accounted for an additional AU$22.9 million in direct surgical costs from 2010 to 2018.