Evidence that the government's multi-billion pound investment in health technology will work is scarce to find, a leading think tank has warned.

A report published by the Institute for Public Policy Research said that while information and communications technology (ICT) should be able to improve care standards, there is a lack of data to prove this is the case.

The Department of Health is currently embarked upon the implementation of three major projects to deliver electronic patient records, electronic booking systems for appointments and the electronic transfer of prescription information.

But the think tank's study struck a cautionary note.

"Despite the clear potential benefits of improving use of ICT, really solid evidence of a positive impact in practice is still quite scarce," said the report.

While more than 40 different evaluation reports were examined, the authors were "surprised by the disparity between the obvious potential benefits of using ICT more effectively in health and the paucity of evidence that these benefits are being delivered in practice".

The report also concluded that public and political support for the investment in health service technology could be undermined without better planning and evaluation.

Trials of electronic patient records failed to demonstrate that they would lead cost savings or improvements in treatment of patients, concluded the IPPR.

And pilots of electronic appointment booking systems have not clearly shown that they facilitate greater choice for patients over where, when and by whom they are treated.

"The potential benefits of ICT use in the health service could be huge and make a real impact on the direct experience of patients and health professionals," said report author Jamie Bend.

"This potential needs to be demonstrated in practice. Unless it's proven that things like electronic health records work, it will remain difficult to justify to doctors, nurses and patients existing and additional spending on ICT.

"Few of the problems with evaluation are new, yet they continue to occur and there is a perception that ICT projects have failed.

"This is not a reason to reject the use of ICT but to redouble efforts to use it effectively."

To tackle the problems, the think tank called for evaluations of ICT projects in health to be clearly linked to the stated aims of the projects, while adequate time and resources should be allocated to evaluation.

It added that appropriate data should be collected to examine the effectiveness of projects.