A newly-launched web tool will allow commissioners to compare how their local out-of-hours service is performing against others around the country.
The Primary Care Foundation's benchmarking tool will include data from 104 of the 151 English primary care trusts and is based on information summarised in over 40 indicators including cost, quality, outcomes, timeliness and patient experience.
"This is a significant step," said Henry Clay, Director of the Primary Care Foundation.
"There are no other areas of healthcare where direct comparison can be made by commissioners, service users and providers of such a range of performance measures, cost and patient perception, nor has it been done before in a way that allows the user to take account of explanatory factors such as deprivation, organisational structure or the nature of the area."
Key findings already obtained by the comparison web tool show the overall performance of out-of-hours services are improving.
In particular, access to services appear "easy and rapid" and cost variations are said to be falling.
However, the Primary Care Foundation claims a lack of data quality makes it "impossible" to "confidently" explain how patients end up in hospital.