IOL has not responded to requests for the sources of these claims. (Note: we will update this report if they do.)
An internet search revealed that both claims come from a 2017 article by the American Association of Obstetricians and Gynecologists.
The article cites two sources for the claim that one in five youth aged nine to 17 has a mental health disorder.
The first is a report by the United States surgeon general from 1999 – more than two decades ago – which in turn relies on data from a 1996 study. The study surveyed almost 1,300 youth aged nine to 17, in four US locations.
The second source is a nationally representative US survey of around 10,000 youth aged 13 to 18, conducted in 2010.
Both studies relied on earlier systems of classifying mental illness. Today, health professionals use the revised fifth version of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5-TR). Some criteria for diagnosing particular disorders have been added or removed from the revised edition. And entire disorders are no longer listed.
Dr Debbie Kaminer, a psychology researcher at the University of Cape Town, told Africa Check that “prevalence rates from the pre-DSM 5 era are likely to be outdated”, particularly for disorders whose diagnostic criteria have changed. (Prevalence is a measure of how common a disease or condition is in a population.)
Both studies were conducted in the US in the previous century, so their results may not apply elsewhere, today. They could have been true in the US in the 1990s. But they are no evidence for global mental health rates in the 2020s.
“One does need to be cautious about generalising data from a US study to other contexts,” Dr Lauren Wild, an associate professor in the University of Cape Town’s psychology department, told Africa Check.
What does more recent data show?
The WHO’s World Mental Health Report, published in 2022, uses data from across the globe to estimate how common mental illness is.
Much of its information is from the 2019 Global Burden of Disease report – a large-scale study using data from over 156 countries. The report is maintained by the Institute for Health Metrics and Evaluation or IHME, an independent global health research centre at the University of Washington in the US.
Africa Check asked the South African Federation for Mental Health (SAFMH), an NGO involved in mental health awareness and advocacy, about the GBD’s accuracy. They told us that despite some limitations, the GBD report provides “the most recent and comprehensive” data available on the global prevalence of mental illness.
According to the report, around 14% of youth aged 10 to 19 live with mental illness. This is around one in seven youth globally – lower than the estimate in the US studies.
The WHO report suggests that mental illness rates are often lower in lower-income countries. But the authors say this may not mean there is less mental illness.
Stigma and discrimination in low-income countries could cause people not to disclose mental illnesses. Ideas of mental illness also differ across cultures. This means ways of describing and measuring mental illness usually used in prevalence studies might not capture the full picture.
South Africa’s ‘alarming risk factors to poor mental health’
Mental illness in South Africa is no less complex, although the country lacks sufficient data on its prevalence. And where studies are available, researchers have criticised their use of “small and unrepresentative samples”, or designs that may not be locally relevant.
Mental health expert Bharti Patel spoke to Africa Check on behalf of SAFMH. Despite the absence of rigorous data, she said, South Africa’s prevalence of mental ill-health could be “far higher” than in the US. South Africa has “alarming risk factors to poor mental health”, such as economic inequality, inequitable access to healthcare, and gender-based violence.
Patel added that it was important to “be mindful of the dynamics of poverty”, a risk factor possibly less common in the US.
Poverty and disease, including HIV and Aids, have been closely linked to mental health. In South Africa, more than 8 million people live with HIV. Research suggests that rates of mental illness are higher among adolescents who have lived with parents affected by HIV, or who have been orphaned by Aids.
A 2021 systematic review summarises evidence from 37 studies – with almost 100,000 participants – across sub-Saharan Africa. It doesn’t give much information about South Africa, but finds that depression and anxiety disorders affected, on average, more than a quarter of the adolescent population in the countries it covers. This is one in four adolescents aged 10 to 19.
An earlier review in six sub-Saharan African countries has a lower estimate – one in seven adolescents.
While the exact numbers are unclear, Patel said the IOL article did get something right: mental illness among adolescents is more common than people realise.
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