Doctors’ fees in Ireland following the change in reimbursement : did they jump?

This paper analyses the pure time-series properties of doctors’ fees in Ireland to assess whether a structural change in the series is observed at the time of the change in reimbursement in 1989. Such a break would be consistent with doctors responding to the reimbursement change in a manner predicted by supplier-induced-demand behaviour and would provide indirect
evidence that such inducement had taken place. Structural change is assessed on the basis of CUSUM and CUSUMSQ tests. The data is also analysed for the presence of unusually influential observations. In neither case are the results consistent with a break around the time of the introduction of the change.