SO IT'S NO DIFFERENT THAN THE REST OF MEDICINE:

The extraordinarily popular DSM-III was revised in 1987. But, by the late 80s, enough new data had been accumulated that a new version was needed. Dr Allen Frances, then chair of psychiatry at Duke University School of Medicine in the US, was chosen to head the DSM-IV task force. The six-year effort involved over 1000 individuals, required extensive review of existing research and field trials of any changes before being published in 1994. But today Frances wonders whether these measures were enough. Rates of mental illness, particularly ADHD and autism, have skyrocketed since the 1990s and Frances believes that the DSM-IV - which has become one of the most widely used texts in psychiatry - is party to blame.

Instead of inadequately treating those who most need assistance, he wonders, are we now spending time and resources treating those who don't need help at all?

THERE HAVE BEEN SEVERAL studies showing rapid increases in diagnoses worldwide, explains Frances, now an emeritus professor at Duke. A 2010 study reported in Psychological Medicine, for example, followed a cohort from Dunedin, New Zealand, and found that half reported at least one anxiety disorder by the age of 32.

A similar study done by Frances' colleagues at Duke University, epidemiologists E. Jane Costello and Adrian Angold, and published in 2011 in the Journal of the American Academy of Child and Adolescent Psychiatry, tested young people for symptoms several times between the ages of 9 and 21. They found that 83% of participants had met criteria for a disorder by 21.

"Either the criteria are way too loose and we're including people who have the normal aches and pains of growing up," says Frances, "or everyone's real sick."

Frances outlines the rapid cycling of diagnostic fads in psychiatry, his own view being that while labels and labellers may change, human nature doesn't. 

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