About £200m is spent each year on deciding which museums or cultural attractions should receive grants, the National Audit Office (NAO) has revealed.

Each year, about £1.8bn is handed out in grants to the culture, media and sport sector, but there are wild discrepancies in the amount of money spent on assessing where the awards should go.

The NAO investigation found the cost of making a grant ranged from £380 to nearly £10,000. It suggested grant-makers "should review whether the costs of making grants are proportionate to the size of grants awarded".

The NAO examined four grant-making bodies, including the Big Lottery Fund. It found assessment costs were highest when specialists such as architects had to evaluate projects.

The report criticised the lack of coordination among grant-makers. It pointed out that grant-makers had developed their own IT systems, but that there was "little evidence" that other lessons learned on costs and process had been shared.