An illness is an illness wherever you are. Perhaps this is true for organic diseases but the cultural background can play a tremendous role in the progression and even diagnosis of mental disorders (see e.g., David Dobbs recent post at Wired). However, what has been neglected is an appreciation of how culture affects the research underlying the diagnosis and treatment of psychological disorders. As a consequence, our view on the disorder can change.
Attention deficit hyperactivity disorder shows how culture can exert quite some effect on psychiatric research. In a 2007 meta-analysis by Polanczyk and colleagues prevalence rates were found to differ markedly between geographic regions, but not in the way you might expect. As opposed to the myth of ADHD as an American social construct, European and North American ADHD rates were not significantly different. But both were significantly different to the prevalence rates in Africa and the Middle East.
However, Polanczyk and colleagues state that this is most likely due to different criteria for diagnosis and study inclusion. For example, while the diagnostic system published by the World Health Organisation is quite strict, the one published by the American Psychiatric Association is more liberal. Depending on which one the researchers adopt, the same person could be part of the ADHD group in one study and the control group in another one.
These different inclusion criteria appear to bias international comparisons. The severe restrictions on ADHD diagnosis in Middle Eastern studies can increase the apparent ADHD severity and social problems. Don’t be surprised then if you read that Middle Eastern ADHD kids fare worse in life than their American counterparts.
Beyond different inclusion criteria, the focus of studies can differ by geographic region. In a recent review, Hodgkins et al. (2012) showed that about half of North American and European ADHD studies sampled adults. East Asian researchers, on the other hand, were mainly interested in adolescents and only sampled adults in about a third of studies. Will this result in ADHD as a potentially life long disease in the Western view while the Easten perspective sees it as part of the transition to adulthood? If so, researchers could be partly to blame for this difference.
Finally, what life consequences a ADHD diagnosis entails is differently researched. While East Asians are mainly interested in effects on self-esteem, Europeans focus more on antisocial behaviour. North American researchers, on the other hand, measure drug abuse and addiction outcomes more than their European or East Asian counterparts. A single headline grabbing result could forever associate inattentive kids with drug abuse. Don’t expect this result to emerge in Asia, it is likely to be found in the US.
This is not to say that ADHD, its prevalence in different age groups or its life consequences are entirely determined by research agendas. Evidence is still needed to support diagnosis or treatment. However, whether anyone ever looked for this evidence is dependent on culture. Across the world research cultures, i.e. strategies to get scientific evidence, differ. Don’t be surprised then if evidence based psychiatry differs as well.
Hodgkins P, Arnold LE, Shaw M, Caci H, Kahle J, Woods AG, & Young S (2011). A systematic review of global publication trends regarding long-term outcomes of ADHD. Frontiers in psychiatry / Frontiers Research Foundation, 2 PMID: 22279437
Polanczyk G, de Lima MS, Horta BL, Biederman J, & Rohde LA (2007). The worldwide prevalence of ADHD: a systematic review and metaregression analysis. The American journal of psychiatry, 164 (6), 942-8 PMID: 17541055
1) By CDC (http://www.cdc.gov/ncbddd/adhd/facts.html) [Public domain], via Wikimedia Commons
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