Research for the Annual Charity Barometer for 2011 measured national and local online and print coverage and broadcast news coverage for 74 of the charities with the highest level of news coverage.
It found that 623,856 articles or broadcast items mentioned one or more of the 74 organisations in 2011. In the previous year, 434,946 items were recorded, but television and radio coverage was not included.
The RSPCA, which came top of the table last year, was in eighth position in the latest report, with 24,283 mentions.
The national online publication most likely to mention charities was The Guardian website; the national print publication most likely to do so was The Daily Telegraph.
Catherine Wright, group account director of the charity team at Metrica, said the report showed that world events had an impact on charities’ media coverage.
"Working with celebrities and public figures has also had a real impact again this year, with fundraising for annual events being boosted by these partnerships, and connections with public figures such as the Duke and Duchess of Cornwall having a positive effect on helping a charity raise its profile and fundraising ability," she said.