The Scottish Government could improve the reliability of official estimates of economic growth by using measures based on the expenditure of key groups including consumers and business, a study says.

Economists at consultancy DTZ said enough data was available in Scotland to produce an expenditure approach measure of gross domestic product that would meet International Monetary Fund standards.

Following a study commissioned by the chief economic adviser to the Scottish Government and the Enterprise Department, experts concluded it should be possible to give a quarterly breakdown of consumer, government and investment expenditure, as well as imports and exports data.

They believe this would give a clearer picture of the Scottish economy than existing methods of estimating growth in GDP, which are based on measuring the volumes of output produced by Scottish entities.

As GDP estimates for the UK and many other states are produced using expenditure data, the use of volume-based measures in Scotland makes it hard to compare performance with that of other countries.

Richard Marsh, author of the report, said an expenditure measure of GDP would put Scotland on a par with other developed countries such as Ireland.

"An expenditure measure of GDP is a fundamental building block for understanding the economy and a current gap in available information. A new series based on this would boost the credibility of Scottish economic statistics and offer greater depth for analysis.

"It would provide a comparative point of view with the UK, an invaluable source of information given how major economic events such as the credit crunch are unfolding differently in Scotland."