Sunday, July 15, 2012

Another bogus statistic on the fear of public speaking

On a web page about speaker training by the Brandi Kamenar Design Studio I read a claim that:

“According to a March 2012 study by the National institute of Mental Health, the number one fear of Americans is the fear of public speaking. At 74 percent, it topped even the fear of dying.”

The same 74% statistic also was reported in an article by Julie Pare, a student at Loyola University Chicago, on How to Become a Better Public Speaker that linked to a web page at the Statistic Brain web site which lists percentages for speech anxiety. On July 1st I blogged about another page at that web site with a bogus list of top ten phobias.

That page at the Statistic Brain site contains a box which says their source was the National Institute of Mental Health (NIMH), and statistics were verified on March 28, 2012. They also listed 75 percent for women and 73 percent for men. On April 26th I emailed the Statistic Brain web site and asked them exactly where those three percentages came from. So far they haven’t bothered to reply.

That page also claimed that 5.3 million Americans suffer from social phobia. Researching that number on Google revealed that it came from an decade old NIMH pamphlet which said that:

“About 3.7% of the U.S. population ages 18 to 54 - approximately 5.3 million Americans - has social phobia in any given year.”

The current NIMH page with statistics on social phobia lists a lifetime prevalence of 12.1% and a 12-month prevalence of 6.8%. So, they hadn’t really checked the current NIMH page at all, which said 6.8% rather than 3.7%. Those NIMH statistics came from the National Comorbidity Survey-Replication (NCS-R).

I have previously blogged about a 2008 article by Ruscio et al that  analyzed data from the NCS-R and reported that 21.2% of U.S. adults feared public speaking. For fear of public speaking the 74% reported on the Statistic Brain page is three and a half times higher than the current NIMH data, as is shown above on a bar chart.

Where did the 73%, 74% and 75% really come from? I don't know, but those sorts of percentages (~75%) were reported decades ago by James C. McCroskey and his colleagues. They certainly aren’t from this year, so they pinned my bogometer.

The bogometer image was derived from this one of a digital multimeter.

UPDATE  February 2014

See Busting a myth - that 75% of people in the world fear public speaking.

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