Last week, the NHS published statistics revealing that one in four teenage girls has self-harmed. This is not only a significant increase from last time such a study was conducted but it is also much higher than the rates of self-harm among boys. Cue an avalanche of missed calls on my phone from television and radio stations inviting me to comment on "proof that girls have worse mental health than boys". I declined them all.

Mental health statistics are endlessly problematic for a number of reasons. In order to collate mental health data, you essentially have two options – look at diagnoses or ask people about their experiences. But only a tiny proportion of people who experience mental health difficulties meet the criteria for diagnosis of mental illness (remembering also that mental health issues are distinct from mental illness). And asking people is tricky when attempting to measure invisible wellbeing criteria – every person has a different baseline for what is emotionally "normal" and expresses their distress in different ways. Then we have the fact that mental health is still shrouded in stigma and shame, particularly among some social, religious and ethnic groups, making some people more likely to "admit" to mental health issues than others.

Deprived of context

Statistics can be a useful barometer, but zoning in on the one most "headliney" stat also deprives us of the ability to see things in context and means we are more likely to jump to erroneous conclusions. Take, for example, when the Department for Education published a report last month showing that one in three young women were experiencing feelings of anxiety and/or depression and that this was particularly prevalent in independent schools. The press ran various headlines declaring categorically that middle-class girls are the most vulnerable to mental illness. They didn’t for one moment stop to consider that perhaps being a girl from a middle-class background might make it easier to discuss feelings of anxiety and depression for all kinds of reasons: less social judgement, more education around the subject and a better emotional vocabulary being just a few.

Adult women are three times more likely to be diagnosed with anxiety or depression. If you write clickbait for the Daily Mail, you might take this statistic in isolation and conclude that anxiety and depression are "female" illnesses. However, men are three times more likely to seek help for drug and alcohol addiction and they are also far more likely to take their own lives. The suicide and addiction stats are important for context – what they tells us is that women are talking about and seeking help for the symptoms of low mood and mental distress, whereas men are self-medicating and waiting until they reach crisis point, often with tragic consequences.

Research conducted by Mental Health First Aid England shows that girls are more likely to be diagnosed with an emotional or mental health issue, but boys are more likely to be labelled as having behavioural difficulties. This is in part owing to prevailing social prejudices about what girls and boys are "like", partly because of inherent differences in the way that girls and boys instinctually react to uncomfortable emotions and partly because it’s more socially acceptable for girls to talk about their feelings. In the words of a very wise teacher "every behaviour is a communication", so what are the boys who are "misbehaving" communicating?

Violence instead of talking

I’ve written previously about masculinity – how we define it as a culture and how our definition usually demands stoicism in the face of adversity. In order to be "proper" men, boys are taught that they must squash their feelings and "deal with" them alone. Violence is more acceptable than talking. The result is a catastrophic trend in men taking their own lives.

The danger zone age-wise for male suicide is between 24 and 35, when it accounts for one in four deaths. This is long after they have left school and, therefore, the focus for teen and school-based interventions has historically been on girls, whose symptoms of emotional distress are discussed and manifest earlier. This is a classic firefighting technique, which doesn’t take into account that perhaps the foundations for suicide being the biggest killer of men under 50 in Britain are laid in childhood and adolescence.

Teachers already know this, of course. When I speak to school staff on the ground, there is a tangible concern about the mental wellbeing of boys. The people who collate statistics don’t spend time with young people every day. For that reason, they can’t paint a comprehensive and reliable picture of the emotional wellbeing of young people in the way that parents and teacher can. Evidence is important, but if we allow our assessment of need to be driven by statistics alone, then it is those who are not able to articulate their need who will suffer. In the case of mental health, that is often our boys.

In the words of a sixth-form girl in an independent school I was chatting to the other week: "Perhaps it would be more helpful if we thought of us middle class girls as spokespeople for our generation, when it comes to mental health."

Natasha Devon is the former government mental health champion for schools and founder of the Body Gossip Education Programme and the Self-Esteem Team. She tweets as @NatashaDevonMBE

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