The controversial new GPs' contract needs to be better managed, the Auditor General for Wales has said.
Jeremy Colman said there should be closer monitoring of the money given out to GP practices in Wales under the terms of the new General Medical Services (GMS) contract.
His report found ambiguity about defining what core services the contract provides, and instances of some GP practices claiming additional income for services they offered under the old contract.
The 62-page document also revealed variance in the "depth and rigour" applied to checking the points awarded to each GP practice under the Quality and Outcomes Framework (QOF), which helps measure performance and distribute funding.
A spokeswoman for the Wales Audit Office said: "Local health boards are not making random checks to ensure that the new system is working properly in Wales, in contrast to the position in England.
"The contract provides a framework for GPs to provide new and enhanced services to patients.
"The report finds the number of these services provided has been limited, apart from some services directed nationally."
The document, Review Of The New General Medical Services Contract In Wales, also recommends that local health boards introduce routine, detailed checks.
It adds that NHS commissioners must make full use of the new contract's flexibilities to provide local services based on local needs.