A new report looks at how 15 key spokespeople communicated during the swine flu crisis. University of London professor of virology John Oxford and Health Secretary Andy Burnham are considered to have performed most effectively during the health scare.
Conversely, the public is far less convinced by spokespeople who appear in a formal setting and fail to provide practical advice.
Prime Minster Gordon Brown was named as the least effective communicator, just ahead of Dr Marie-Paule Kieny and Gregory Hart, both from the World Health Organization.
The report, called Swine Flu: Getting the message through, was compiled by Insignia Communications director Jonathan Hemus and the University of Wolverhampton.
Members of the public were shown 15 media interviews and speeches about swine flu and asked for their views on each spokesperson. Researchers analysed four focus groups containing 38 people to determine their reactions.
'The most effective spokesman, professor John Oxford, combined a senior academic background and a formal appearance ... with a personable style and clear actionable advice,' said Hemus. 'Gordon Brown suffered from poor body language, a lack of practical advice and a formal setting which sent a subliminal message of a crisis situation.'
The report also found credible spokespeople, including doctors, scientists and academics, who provide worrying insights without clear advice, can cause public anxiety.
Burnham was named second most effective, while Roy Anderson of Imperial College came third and Tom Jefferson of The Cochrane Collaboration came fourth. The Government's chief medical officer, Sir Liam Donaldson, ranked number five in the list.
'High-profile spokespeople have enormous power to reassure and inform the public,' said Hemus. 'Equally, they have the ability to cause unnecessary confusion and distress.'