.:[Double Click To][Close]:.

Saturday, January 24, 2009

The British are Incredibly Sad

Or so says Oliver James(*) on this BBC radio show in which he also says things like "I absolutely embraces the credit crunch with both arms".

Oliver James is a British psychologist best known for his theory of "Affluenza". This is his term for unhappiness and mental illness caused, he thinks, by an obsession with money, status and possessions. Affluenza, James thinks, is especially prevanlent in English-speaking countries, because we're more into free-market capitalism than the people of mainland Europe. In fact, he regularly makes the claim that we in Britain, the U.S., Australia etc. are today twice as likely to be mentally ill as "the Europeans". This is because rates of mental illness supposedly surged in the English-speaking world due to 1980s Reagan/Thatcher free market policies. Hence why he welcomes the current economic unpleasantness.

Were all of this true, it would be incredibly important. Certainly important enough to justify writing three books about it and seemingly endless articles for the Guardian. But is it true? Well, this is Neuroskeptic, so you can probably guess. Also, bear in mind that James is someone who is on record as thinking that
[The Tears for Fears song] Mad World. With the chilling line "The dreams in which I'm dying are the best I've ever had", in some respects it is up there with TS Eliot's Prufrock as a poetic account of bourgeois despair.
Obviously poetic taste is entirely subjective etc., but honestly.

Anyway, where did James get the twice-as-bad-as-Europe (or, in some articles, three times as bad) idea from? He says the World Health Organization. Presumably he is referring to one of the World Health Organization's World Mental Health Surveys, such as the analysus presented in this JAMA paper.

At first glance, you can see what he means. This paper reports that the % of people reporting suffering from at least one mental illness over the last year was far higher in the US (26.4%) than in say Italy (8.2%), or Nigeria (4.7%). But on closer inspection, even this data includes some incongruous numbers. Why is Beijing (9.1%) twice as bad as Shanghai (4.3%)? Worse, why does France have a rate of 18.4% while across the border in Germany it's just 9.1%? Are the French twice as materialistic as the Germans? The answer, of course, is that these numbers are more complicated than they appear. In fact, if you believe those figures at face value, you are...well, you're probably Oliver James.

These numbers come from structured interviews, conducted by trained lay researchers, of a random sample of the population. In other words, some guy asked some random people a series of fairly personal questions, reading them off a list, and if they said "Yes" to questions like "Have you ever in your life had a period lasting several days or longer when most of the day you felt sad, empty or depressed?" they might get a tick for "depression". We know this because the interviews used the WHO-CIDI screening questionaire, the first part of which is here.

As part of my own research, I have been that guy asking the questions (in a slightly different context). At some point I'll write about this in more detail, but suffice to say that it's hard to trying to retrospectively diagnose mental illness in someone you've never met before. The potential for denial, mis-remembering, malingering, forgetting or just plain failure to understand the questions is enormous, although it doesn't come across in the final data, which looks lovely and neat.

The authors of the JAMA paper are well aware of this which is why they're skeptical of the apparantly large cross-national differences. In fact, most of their comment section consists of caveats to that effect. Just a few (edited, emphasis mine - see the full paper for more, it's free):
An important limitation of the WMH surveys is their wide variation in response rate. In addition, some of the surveys had response rates below normally accepted standards [i.e. many people refused to participate]... performance of the WMH-CIDI could be worse in other parts of the world either because the concepts and phrases used to describe mental syndromes are less consonant with cultural concepts than in developed Western countries [almost certainly they are] or because absence of a tradition of free speech and anonymous public opinion surveying causes greater reluctance to admit emotional or substance-abuse problems than in developed Western countries. [again, almost certainly, and Europeans are generally more reserved than Americans in this regard.] ... some patterns in the data (e.g. the much lower estimated rate of alcoholism in Ukraine than expected from administrative data documenting an important role of alcoholism in mortality in that country) raise concerns about differential validity.
There's another, more fundamental problem with this data. On any meaningful criterion of "mental illness", a society in which 25% people were mentally ill in any given year would probably collapse. The WHO survey, however, is based on the DSM-IV criteria of mental illness. These are are increasingly regarded as very broad; for example, DSM-IV does not distinguish between feeling miserable & down for two weeks because your boyfriend leaves you, and spending a month in bed hardly eating for no apparant reason. Both are classed as "depression", and hence a "mental illness", although 50 years ago, only the second would have been considered a disease. For someone who styles himself a rebel in the mould of R. D. Laing, it's baffling that James accepts the American Psychiatric Association's dubious criteria.

What other data could we look at? Ideally, we want a measure of mental illness which is meaningful, objective and unambigious. Well, there aren't any, but suicide rates might be the next best thing - they're nice hard numbers which are difficult to fudge (although in cultures in which suicide is strongly taboo, suicides may be reported as deaths from other causes.) Although not everyone who commits suicide is mentally ill, it is fair to say that if Britain really were twice as unhappy as the rest of Europe, we would have a relatively high suicide rate.

What's the data? Well, according to Chishti et. al. (2003) Suicide Mortality in the European Union, we don't.
In fact suicide rates in the UK are boringly middle of the road. They're higher than in places like Greece and Spain, but well below rates in France, Sweden and Germany. Suicide rates are not a direct measure of rates of mental illness, because not everyone who commits suicide is mentally ill, and the rate of succesful suicide depends upon access to lethal means. But does this data look compatible with James's claim that rates of "mental illness" are twice as high in Britain as on "the Continent"? - or indeed with James's implicit assumption that "the Continent" is monolithic?

What's odd is that James clearly knows a bit about suicide, or at least he does now, because just today he wrote a remarkably sensible article about suicide statistics for the Guardian. So he really ought to know better.

Drug sales are another nice, hard number. Of course, medication rates do not equal illness rates - in any field of medicine, but especially psychiatry. Doctors in some countries may be more willing to use drugs, or patients may be more willing to take them. With that in mind, the fact that population-adjusted (source, also here) British sales of antidepressants drugs are twice those of Ireland and Italy, equal to those of Spain, and half those of France, Norway and Sweden does not necessarily mean very much. But it hardly supports James's theory either.

Interestingly, although James holds up Denmark as an example of the kind of happy, "unselfish capitalism" that we should aspire to, the Danes take 50% more antidepressants than we do! (They also have a much higher suicide rate.) True, sales of anxiety drugs and sleeping pills are relatively high in the UK, but still less than Denmark's. Most interestingly, sales of antipsychotics are very low in the UK - roughly the same as in Germany and Italy but less than a quarter of the sales in Ireland and Finland!

So cheer up, Anglos. We're not twice as sad as the French. More likely, we are just more open about talking our problems in the interests of scientific research. However, the French, to their credit, didn't give the world Oliver James.

[BPSDB]

(*) This is Oliver James, psychologist. Not to be confused with: Oliver James, heartthrob actor; Oliver James, Fleet Foxes song, and Oliver James, Ltd.

ResearchBlogging.orgThe WHO World Mental Health Survey Consortium (2004). Prevalence, Severity, and Unmet Need for Treatment of Mental Disorders in the World Health Organization World Mental Health Surveys JAMA: The Journal of the American Medical Association, 291 (21), 2581-2590 DOI: 10.1001/jama.291.21.2581

No comments:

Post a Comment