A lack of structure in the government's transparency initiatives could mislead potential users of its open data, according to the National Audit Office (NAO).
In reviewing how the government is fulfilling its commitments to promote the transparency of public information, the NAO noted: "Many data releases have no accompanying statement as to their quality or reliability - running the risk of misleading potential users."
It suggested: "The government should develop a simple protocol for describing data sources, control procedures and known limitations."
Since announcing the transparency agenda in May 2010, the government has released 7,865 data sets (as of December 2011) on Data.gov.uk.
While generally supportive of the aims of the transparency agenda to improve accountability, the NAO did not believe that the government has the proper cost analysis structure in place yet, to get the most value out of the initiatives.
Levels of public interest in the different types of information released varied greatly - with some attracting significantly more attention than others.
For example, the police crime map website had an estimated 47 million visits between February and December 2011, and the Department for Education (DfE) reported an 84 percent increase in the use of its comparative schools data.
Standard releases of data required of all departments - such as information on spending over £25,000 - attracted less interest for other departments, however. Meanwhile, more than four-fifths of visitors to the Data.gov.uk leave the site immediately without accessing any further links, although these users may be accessing the data from other sources.
Amyas Morse, head of the NAO, said: "Opening up access to public information has the potential to improve accountability and support public service improvement and economic growth.
"What the government is lacking at the moment is a firm grasp of whether that potential is being realised. If transparency initiatives are to be more than aspirations, then government needs to measure and monitor both their costs and benefits. This is vital for tracking success and learning what works."