Monday, August 1, 2011

Lists where the fear of public speaking isn’t anywhere near the top - The Epidemiologic Catchment Area Study

Back in the late 1970s the National Institute of Mental Health was trying to figure out how common various mental health problems were. Instead of trying to do a gigantic survey with a nationwide U.S. random sample they chose to do a series of five studies at different research universities located in major metropolitan areas. Each university studied a sample of about 4000 people drawn from the area they served. That geographical area is called a catchment( in analogy to a watershed). Thus the study was called the Epidemiologic Catchment Area (or ECA) Study. Those universities,  their catchment areas, and some study dates were:

Yale University, New Haven Connecticut (1980-81)
Johns Hopkins University, Baltimore, Maryland (1981)
Washington University, St. Louis, Missouri (1981-82, etc.)
Duke University, Durham, North Carolina
UCLA, Los Angeles, California

Results from the studies eventually were published in over a hundred scientific articles. In 1991 results from the entire series were discussed in a 450-page book titled Psychiatric Disorders in America: the epidemiologic catchment area study, edited by Lee N. Robins and Darrel A. Regier. Chapter 7 on Panic and Phobia was written by William W. Eaton, Amy Dryman, and Myrna M. Weissman.

Table 7-5a on page 166 listed the results for lifetime prevalence of both non-severe and severe anxiety symptoms. At Yale there apparently was a mix-up, and they didn’t ask all the questions for every item. That dropped the sample size to only 14,263 people, which still is more than five times as large as the 2,543 people for the endlessly quoted survey reported in the 1977 Book of Lists.    












The bar chart shown above lists the 14 mild (non-severe) anxiety symptoms. (Point and click on it to see a larger, clearer version). Anxiety about bugs, mice, snakes and bats was 1st (16.3%). Anxiety about public speaking was 8th (4.7%), and speaking to new acquaintances was 10th (3.3%). The modest percentages probably are why you haven’t seen these survey results before. They don’t exactly scream out that you’re dealing with a major problem requiring a public speaking class or expensive coaching. 











Another bar chart, shown above, lists the severe symptoms. Anxiety about public speaking was 9th (1.8%), and speaking to new acquaintances (1.4%) was in a three-way tie for 10th.  Severe symptoms (basically phobias) were defined as follows:

“Severe symptoms are those meeting one of three criteria: a professional was told about it, medication was taken for it more than once, or it interfered with life or activities a lot.”












A third bar chart shows the total from adding the severe and non-severe categories. Anxiety about public speaking was 9th (6.5%), and speaking to new acquaintances (4.7%) was 10th. The order for the first nine fears in this chart matches the sequence listed by Bill Tancer in Chapter 6 of his Click book, which I mentioned in a post on July 22nd. This list really isn’t a list of phobias as Mr. Tancer said, and it came from the ECA, not the National Comorbidity Survey (NCS).

What can we learn from digging up this data? First, that there is excellent information you may not have ever seen. (I couldn’t find a copy of the book in Boise, so the public library got me one via interlibrary loan). Like Las Vegas, what happens in psychiatry stays in psychiatry. Second, the terms in a survey may not mean what you think they mean, like speaking in public. Here is the general phobia question and the 14 situations:

“Some people have phobias, that is, such a strong fear of something or some situation that they try to avoid it, even though they know there is no real danger. Have you ever had such an unreasonable fear of (SITUATION) that you tried to avoid (it/them)?

Heights

Tunnels or bridges 

Crowds - being in a crowd

Public transport - being on any kind of public transportation like airplanes, buses, or elevators

Going out by oneself - going out of the house alone

Closed places - being in a closed place

Being alone

Eating in public - eating in front of other people you know (or in public)

Speaking in public - speaking in front of small group of people you know

Speaking to new acquaintances - speaking to strangers or meeting new people

Storms

Water - being in water, for instance in a swimming pool or lake

Spiders, bugs, mice, snakes or bats

Animals - being near any (other) harmless animal or a dangerous animal that couldn’t get to you.”


Third, psychiatry learns and changes. Diagnostic categories and criteria got revised in going from the DSM-III used in the ECA to DSM-IV used in the NCS. Meanwhile, the speaking coaches kept on referring back to that 1977 Book of Lists.

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